diff --git a/Documentation/rest-api-groups.txt b/Documentation/rest-api-groups.txt
index 657f498..7eac992 100644
--- a/Documentation/rest-api-groups.txt
+++ b/Documentation/rest-api-groups.txt
@@ -116,7 +116,7 @@
 
 [[includes]]
 --
-* `INCLUDES`: include list of directly included groups.
+* `INCLUDES`: include list of direct subgroups.
 --
 
 [[members]]
@@ -1129,13 +1129,13 @@
   ]
 ----
 
-[[delete-group-member]]
-=== Delete Group Member
+[[remove-group-member]]
+=== Remove Group Member
 --
 'DELETE /groups/link:#group-id[\{group-id\}]/members/link:rest-api-accounts.html#account-id[\{account-id\}]'
 --
 
-Deletes a user from a Gerrit internal group.
+Removes a user from a Gerrit internal group.
 
 .Request
 ----
@@ -1147,15 +1147,15 @@
   HTTP/1.1 204 No Content
 ----
 
-[[delete-group-members]]
-=== Delete Group Members
+[[remove-group-members]]
+=== Remove Group Members
 --
 'POST /groups/link:#group-id[\{group-id\}]/members.delete'
 --
 
-Delete one or several users from a Gerrit internal group.
+Removes one or several users from a Gerrit internal group.
 
-The users to be deleted from the group must be provided in the request
+The users to be removed from the group must be provided in the request
 body as a link:#members-input[MembersInput] entity.
 
 .Request
@@ -1176,16 +1176,16 @@
   HTTP/1.1 204 No Content
 ----
 
-[[group-include-endpoints]]
-== Group Include Endpoints
+[[subgroup-endpoints]]
+== Subgroup Endpoints
 
-[[included-groups]]
-=== List Included Groups
+[[list-subgroups]]
+=== List Subgroups
 --
 'GET /groups/link:#group-id[\{group-id\}]/groups/'
 --
 
-Lists the directly included groups of a group.
+Lists the direct subgroups of a group.
 
 As result a list of link:#group-info[GroupInfo] entries is returned.
 The entries in the list are sorted by group name and UUID.
@@ -1217,13 +1217,13 @@
   ]
 ----
 
-[[get-included-group]]
-=== Get Included Group
+[[get-subgroup]]
+=== Get Subgroup
 --
 'GET /groups/link:#group-id[\{group-id\}]/groups/link:#group-id[\{group-id\}]'
 --
 
-Retrieves an included group.
+Retrieves a subgroup.
 
 .Request
 ----
@@ -1231,7 +1231,7 @@
 ----
 
 As response a link:#group-info[GroupInfo] entity is returned that
-describes the included group.
+describes the subgroup.
 
 .Response
 ----
@@ -1253,13 +1253,13 @@
   }
 ----
 
-[[include-group]]
-=== Include Group
+[[add-subgroup]]
+=== Add Subgroup
 --
 'PUT /groups/link:#group-id[\{group-id\}]/groups/link:#group-id[\{group-id\}]'
 --
 
-Includes an internal or external group into a Gerrit internal group.
+Adds an internal or external group as subgroup to a Gerrit internal group.
 External groups must be specified using the UUID.
 
 .Request
@@ -1268,7 +1268,7 @@
 ----
 
 As response a link:#group-info[GroupInfo] entity is returned that
-describes the included group.
+describes the subgroup.
 
 .Response
 ----
@@ -1290,11 +1290,11 @@
   }
 ----
 
-The request also succeeds if the group is already included in this
-group, but then the HTTP response code is `200 OK`.
+The request also succeeds if the group is already a subgroup of this
+group.
 
-[[include-groups]]
-=== Include Groups
+[[add-subgroups]]
+=== Add Subgroups
 --
 'POST /groups/link:#group-id[\{group-id\}]/groups'
 --
@@ -1305,10 +1305,10 @@
 'POST /groups/link:#group-id[\{group-id\}]/groups.add'
 --
 
-Includes one or several groups into a Gerrit internal group.
+Adds one or several groups as subgroups to a Gerrit internal group.
 
-The groups to be included into the group must be provided in the
-request body as a link:#groups-input[GroupsInput] entity.
+The subgroups to be added must be provided in the request body as a
+link:#groups-input[GroupsInput] entity.
 
 .Request
 ----
@@ -1327,8 +1327,8 @@
 returned that describes the groups that were specified in the
 link:#groups-input[GroupsInput]. A link:#group-info[GroupInfo] entity
 is returned for each group specified in the input, independently of
-whether the group was newly included into the group or whether the
-group was already included in the group.
+whether the group was newly added as subgroup or whether the
+group was already a subgroup of the group.
 
 .Response
 ----
@@ -1363,13 +1363,13 @@
   ]
 ----
 
-[[delete-included-group]]
-=== Delete Included Group
+[[remove-subgroup]]
+=== Remove Subgroup
 --
 'DELETE /groups/link:#group-id[\{group-id\}]/groups/link:#group-id[\{group-id\}]'
 --
 
-Deletes an included group from a Gerrit internal group.
+Removes a subgroup from a Gerrit internal group.
 
 .Request
 ----
@@ -1381,16 +1381,16 @@
   HTTP/1.1 204 No Content
 ----
 
-[[delete-included-groups]]
-=== Delete Included Groups
+[[remove-subgroups]]
+=== Remove Subgroups
 --
 'POST /groups/link:#group-id[\{group-id\}]/groups.delete'
 --
 
-Delete one or several included groups from a Gerrit internal group.
+Removes one or several subgroups from a Gerrit internal group.
 
-The groups to be deleted from the group must be provided in the request
-body as a link:#groups-input[GroupsInput] entity.
+The subgroups to be removed must be provided in the request body as a
+link:#groups-input[GroupsInput] entity.
 
 .Request
 ----
@@ -1495,9 +1495,9 @@
 entities describing the direct members. +
 Only set if link:#members[members] are requested.
 |`includes`    |optional, only for internal groups|
-A list of link:#group-info[GroupInfo] entities describing the directly
-included groups. +
-Only set if link:#includes[included groups] are requested.
+A list of link:#group-info[GroupInfo] entities describing the direct
+subgroups. +
+Only set if link:#includes[subgroups] are requested.
 |===========================
 
 The type of a group can be deduced from the group's UUID:
diff --git a/gerrit-extension-api/src/main/java/com/google/gerrit/extensions/api/groups/GroupApi.java b/gerrit-extension-api/src/main/java/com/google/gerrit/extensions/api/groups/GroupApi.java
index 0d4742b..fe85eaa 100644
--- a/gerrit-extension-api/src/main/java/com/google/gerrit/extensions/api/groups/GroupApi.java
+++ b/gerrit-extension-api/src/main/java/com/google/gerrit/extensions/api/groups/GroupApi.java
@@ -109,15 +109,15 @@
   void removeMembers(String... members) throws RestApiException;
 
   /**
-   * List included groups.
+   * Lists the subgroups of this group.
    *
-   * @return included groups.
+   * @return the found subgroups
    * @throws RestApiException
    */
   List<GroupInfo> includedGroups() throws RestApiException;
 
   /**
-   * Add groups to be included in this one.
+   * Adds subgroups to this group.
    *
    * @param groups list of group identifiers, in any format accepted by {@link Groups#id(String)}
    * @throws RestApiException
@@ -125,7 +125,7 @@
   void addGroups(String... groups) throws RestApiException;
 
   /**
-   * Remove included groups from this one.
+   * Removes subgroups from this group.
    *
    * @param groups list of group identifiers, in any format accepted by {@link Groups#id(String)}
    * @throws RestApiException
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupCacheImpl.java b/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupCacheImpl.java
index b567409..2901501 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupCacheImpl.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupCacheImpl.java
@@ -239,9 +239,9 @@
 
         ImmutableSet<Account.Id> members =
             groups.getMembers(db, groupUuid).collect(toImmutableSet());
-        ImmutableSet<AccountGroup.UUID> includes =
-            groups.getIncludes(db, groupUuid).collect(toImmutableSet());
-        return accountGroup.map(group -> InternalGroup.create(group, members, includes));
+        ImmutableSet<AccountGroup.UUID> subgroups =
+            groups.getSubgroups(db, groupUuid).collect(toImmutableSet());
+        return accountGroup.map(group -> InternalGroup.create(group, members, subgroups));
       }
     }
   }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupIncludeCacheImpl.java b/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupIncludeCacheImpl.java
index 0d45397..10c002c0 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupIncludeCacheImpl.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupIncludeCacheImpl.java
@@ -150,7 +150,7 @@
     public ImmutableList<AccountGroup.UUID> load(AccountGroup.UUID key)
         throws OrmException, NoSuchGroupException {
       try (ReviewDb db = schema.open()) {
-        return groups.getIncludes(db, key).collect(toImmutableList());
+        return groups.getSubgroups(db, key).collect(toImmutableList());
       }
     }
   }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupMembers.java b/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupMembers.java
index 496b364..4dc960d 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupMembers.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupMembers.java
@@ -117,7 +117,7 @@
 
     Set<Account> indirectMembers = new HashSet<>();
     if (groupControl.canSeeGroup()) {
-      for (AccountGroup.UUID subgroupUuid : group.getIncludes()) {
+      for (AccountGroup.UUID subgroupUuid : group.getSubgroups()) {
         if (!seen.contains(subgroupUuid)) {
           indirectMembers.addAll(listAccounts(subgroupUuid, project, seen));
         }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/account/IncludingGroupMembership.java b/gerrit-server/src/main/java/com/google/gerrit/server/account/IncludingGroupMembership.java
index 87871d0..ae28e1c 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/account/IncludingGroupMembership.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/account/IncludingGroupMembership.java
@@ -97,7 +97,7 @@
         if (!group.isPresent()) {
           continue;
         }
-        if (search(group.get().getIncludes())) {
+        if (search(group.get().getSubgroups())) {
           memberOf.put(id, true);
           return true;
         }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/api/groups/GroupApiImpl.java b/gerrit-server/src/main/java/com/google/gerrit/server/api/groups/GroupApiImpl.java
index 84f4535..42213f7 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/api/groups/GroupApiImpl.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/api/groups/GroupApiImpl.java
@@ -22,10 +22,10 @@
 import com.google.gerrit.extensions.common.GroupInfo;
 import com.google.gerrit.extensions.common.GroupOptionsInfo;
 import com.google.gerrit.extensions.restapi.RestApiException;
-import com.google.gerrit.server.group.AddIncludedGroups;
 import com.google.gerrit.server.group.AddMembers;
-import com.google.gerrit.server.group.DeleteIncludedGroups;
+import com.google.gerrit.server.group.AddSubgroups;
 import com.google.gerrit.server.group.DeleteMembers;
+import com.google.gerrit.server.group.DeleteSubgroups;
 import com.google.gerrit.server.group.GetAuditLog;
 import com.google.gerrit.server.group.GetDescription;
 import com.google.gerrit.server.group.GetDetail;
@@ -35,8 +35,8 @@
 import com.google.gerrit.server.group.GetOwner;
 import com.google.gerrit.server.group.GroupResource;
 import com.google.gerrit.server.group.Index;
-import com.google.gerrit.server.group.ListIncludedGroups;
 import com.google.gerrit.server.group.ListMembers;
+import com.google.gerrit.server.group.ListSubgroups;
 import com.google.gerrit.server.group.PutDescription;
 import com.google.gerrit.server.group.PutName;
 import com.google.gerrit.server.group.PutOptions;
@@ -64,9 +64,9 @@
   private final ListMembers listMembers;
   private final AddMembers addMembers;
   private final DeleteMembers deleteMembers;
-  private final ListIncludedGroups listGroups;
-  private final AddIncludedGroups addGroups;
-  private final DeleteIncludedGroups deleteGroups;
+  private final ListSubgroups listSubgroups;
+  private final AddSubgroups addSubgroups;
+  private final DeleteSubgroups deleteSubgroups;
   private final GetAuditLog getAuditLog;
   private final GroupResource rsrc;
   private final Index index;
@@ -86,9 +86,9 @@
       ListMembers listMembers,
       AddMembers addMembers,
       DeleteMembers deleteMembers,
-      ListIncludedGroups listGroups,
-      AddIncludedGroups addGroups,
-      DeleteIncludedGroups deleteGroups,
+      ListSubgroups listSubgroups,
+      AddSubgroups addSubgroups,
+      DeleteSubgroups deleteSubgroups,
       GetAuditLog getAuditLog,
       Index index,
       @Assisted GroupResource rsrc) {
@@ -105,9 +105,9 @@
     this.listMembers = listMembers;
     this.addMembers = addMembers;
     this.deleteMembers = deleteMembers;
-    this.listGroups = listGroups;
-    this.addGroups = addGroups;
-    this.deleteGroups = deleteGroups;
+    this.listSubgroups = listSubgroups;
+    this.addSubgroups = addSubgroups;
+    this.deleteSubgroups = deleteSubgroups;
     this.getAuditLog = getAuditLog;
     this.index = index;
     this.rsrc = rsrc;
@@ -233,27 +233,27 @@
   @Override
   public List<GroupInfo> includedGroups() throws RestApiException {
     try {
-      return listGroups.apply(rsrc);
+      return listSubgroups.apply(rsrc);
     } catch (Exception e) {
-      throw asRestApiException("Cannot list included groups", e);
+      throw asRestApiException("Cannot list subgroups", e);
     }
   }
 
   @Override
   public void addGroups(String... groups) throws RestApiException {
     try {
-      addGroups.apply(rsrc, AddIncludedGroups.Input.fromGroups(Arrays.asList(groups)));
+      addSubgroups.apply(rsrc, AddSubgroups.Input.fromGroups(Arrays.asList(groups)));
     } catch (Exception e) {
-      throw asRestApiException("Cannot add group members", e);
+      throw asRestApiException("Cannot add subgroups", e);
     }
   }
 
   @Override
   public void removeGroups(String... groups) throws RestApiException {
     try {
-      deleteGroups.apply(rsrc, AddIncludedGroups.Input.fromGroups(Arrays.asList(groups)));
+      deleteSubgroups.apply(rsrc, AddSubgroups.Input.fromGroups(Arrays.asList(groups)));
     } catch (Exception e) {
-      throw asRestApiException("Cannot remove group members", e);
+      throw asRestApiException("Cannot remove subgroups", e);
     }
   }
 
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/group/AddIncludedGroups.java b/gerrit-server/src/main/java/com/google/gerrit/server/group/AddSubgroups.java
similarity index 78%
rename from gerrit-server/src/main/java/com/google/gerrit/server/group/AddIncludedGroups.java
rename to gerrit-server/src/main/java/com/google/gerrit/server/group/AddSubgroups.java
index d777244..2ce168f 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/group/AddIncludedGroups.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/group/AddSubgroups.java
@@ -29,7 +29,7 @@
 import com.google.gerrit.reviewdb.client.AccountGroup;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.account.GroupControl;
-import com.google.gerrit.server.group.AddIncludedGroups.Input;
+import com.google.gerrit.server.group.AddSubgroups.Input;
 import com.google.gwtorm.server.OrmException;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
@@ -41,7 +41,7 @@
 import java.util.Set;
 
 @Singleton
-public class AddIncludedGroups implements RestModifyView<GroupResource, Input> {
+public class AddSubgroups implements RestModifyView<GroupResource, Input> {
   public static class Input {
     @DefaultInput String _oneGroup;
 
@@ -73,7 +73,7 @@
   private final GroupJson json;
 
   @Inject
-  public AddIncludedGroups(
+  public AddSubgroups(
       GroupsCollection groupsCollection,
       Provider<ReviewDb> db,
       @UserInitiated Provider<GroupsUpdate> groupsUpdateProvider,
@@ -98,30 +98,30 @@
     }
 
     List<GroupInfo> result = new ArrayList<>();
-    Set<AccountGroup.UUID> includedGroupUuids = new HashSet<>();
-    for (String includedGroup : input.groups) {
-      GroupDescription.Basic d = groupsCollection.parse(includedGroup);
-      includedGroupUuids.add(d.getGroupUUID());
-      result.add(json.format(d));
+    Set<AccountGroup.UUID> subgroupUuids = new HashSet<>();
+    for (String subgroupIdentifier : input.groups) {
+      GroupDescription.Basic subgroup = groupsCollection.parse(subgroupIdentifier);
+      subgroupUuids.add(subgroup.getGroupUUID());
+      result.add(json.format(subgroup));
     }
 
     AccountGroup.UUID groupUuid = group.getGroupUUID();
     try {
-      groupsUpdateProvider.get().addIncludedGroups(db.get(), groupUuid, includedGroupUuids);
+      groupsUpdateProvider.get().addSubgroups(db.get(), groupUuid, subgroupUuids);
     } catch (NoSuchGroupException e) {
       throw new ResourceNotFoundException(String.format("Group %s not found", groupUuid));
     }
     return result;
   }
 
-  static class PutIncludedGroup implements RestModifyView<GroupResource, PutIncludedGroup.Input> {
+  static class PutSubgroup implements RestModifyView<GroupResource, PutSubgroup.Input> {
     static class Input {}
 
-    private final AddIncludedGroups put;
+    private final AddSubgroups addSubgroups;
     private final String id;
 
-    PutIncludedGroup(AddIncludedGroups put, String id) {
-      this.put = put;
+    PutSubgroup(AddSubgroups addSubgroups, String id) {
+      this.addSubgroups = addSubgroups;
       this.id = id;
     }
 
@@ -129,10 +129,10 @@
     public GroupInfo apply(GroupResource resource, Input input)
         throws AuthException, MethodNotAllowedException, ResourceNotFoundException, OrmException,
             IOException {
-      AddIncludedGroups.Input in = new AddIncludedGroups.Input();
+      AddSubgroups.Input in = new AddSubgroups.Input();
       in.groups = ImmutableList.of(id);
       try {
-        List<GroupInfo> list = put.apply(resource, in);
+        List<GroupInfo> list = addSubgroups.apply(resource, in);
         if (list.size() == 1) {
           return list.get(0);
         }
@@ -144,18 +144,16 @@
   }
 
   @Singleton
-  static class UpdateIncludedGroup
-      implements RestModifyView<IncludedGroupResource, PutIncludedGroup.Input> {
-    private final Provider<GetIncludedGroup> get;
+  static class UpdateSubgroup implements RestModifyView<SubgroupResource, PutSubgroup.Input> {
+    private final Provider<GetSubgroup> get;
 
     @Inject
-    UpdateIncludedGroup(Provider<GetIncludedGroup> get) {
+    UpdateSubgroup(Provider<GetSubgroup> get) {
       this.get = get;
     }
 
     @Override
-    public GroupInfo apply(IncludedGroupResource resource, PutIncludedGroup.Input input)
-        throws OrmException {
+    public GroupInfo apply(SubgroupResource resource, PutSubgroup.Input input) throws OrmException {
       // Do nothing, the group is already included.
       return get.get().apply(resource);
     }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/group/DeleteIncludedGroups.java b/gerrit-server/src/main/java/com/google/gerrit/server/group/DeleteSubgroups.java
similarity index 78%
rename from gerrit-server/src/main/java/com/google/gerrit/server/group/DeleteIncludedGroups.java
rename to gerrit-server/src/main/java/com/google/gerrit/server/group/DeleteSubgroups.java
index 9d296db..14df51b 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/group/DeleteIncludedGroups.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/group/DeleteSubgroups.java
@@ -26,7 +26,7 @@
 import com.google.gerrit.reviewdb.client.AccountGroup;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.account.GroupControl;
-import com.google.gerrit.server.group.AddIncludedGroups.Input;
+import com.google.gerrit.server.group.AddSubgroups.Input;
 import com.google.gwtorm.server.OrmException;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
@@ -36,13 +36,13 @@
 import java.util.Set;
 
 @Singleton
-public class DeleteIncludedGroups implements RestModifyView<GroupResource, Input> {
+public class DeleteSubgroups implements RestModifyView<GroupResource, Input> {
   private final GroupsCollection groupsCollection;
   private final Provider<ReviewDb> db;
   private final Provider<GroupsUpdate> groupsUpdateProvider;
 
   @Inject
-  DeleteIncludedGroups(
+  DeleteSubgroups(
       GroupsCollection groupsCollection,
       Provider<ReviewDb> db,
       @UserInitiated Provider<GroupsUpdate> groupsUpdateProvider) {
@@ -65,15 +65,15 @@
           String.format("Cannot delete groups from group %s", internalGroup.getName()));
     }
 
-    Set<AccountGroup.UUID> internalGroupsToRemove = new HashSet<>();
-    for (String includedGroup : input.groups) {
-      GroupDescription.Basic d = groupsCollection.parse(includedGroup);
-      internalGroupsToRemove.add(d.getGroupUUID());
+    Set<AccountGroup.UUID> subgroupsToRemove = new HashSet<>();
+    for (String subgroupIdentifier : input.groups) {
+      GroupDescription.Basic subgroup = groupsCollection.parse(subgroupIdentifier);
+      subgroupsToRemove.add(subgroup.getGroupUUID());
     }
 
     AccountGroup.UUID groupUuid = internalGroup.getGroupUUID();
     try {
-      groupsUpdateProvider.get().deleteIncludedGroups(db.get(), groupUuid, internalGroupsToRemove);
+      groupsUpdateProvider.get().removeSubgroups(db.get(), groupUuid, subgroupsToRemove);
     } catch (NoSuchGroupException e) {
       throw new ResourceNotFoundException(String.format("Group %s not found", groupUuid));
     }
@@ -82,22 +82,21 @@
   }
 
   @Singleton
-  static class DeleteIncludedGroup
-      implements RestModifyView<IncludedGroupResource, DeleteIncludedGroup.Input> {
+  static class DeleteSubgroup implements RestModifyView<SubgroupResource, DeleteSubgroup.Input> {
     static class Input {}
 
-    private final Provider<DeleteIncludedGroups> delete;
+    private final Provider<DeleteSubgroups> delete;
 
     @Inject
-    DeleteIncludedGroup(Provider<DeleteIncludedGroups> delete) {
+    DeleteSubgroup(Provider<DeleteSubgroups> delete) {
       this.delete = delete;
     }
 
     @Override
-    public Response<?> apply(IncludedGroupResource resource, Input input)
+    public Response<?> apply(SubgroupResource resource, Input input)
         throws AuthException, MethodNotAllowedException, UnprocessableEntityException, OrmException,
             ResourceNotFoundException, IOException {
-      AddIncludedGroups.Input in = new AddIncludedGroups.Input();
+      AddSubgroups.Input in = new AddSubgroups.Input();
       in.groups = ImmutableList.of(resource.getMember().get());
       return delete.get().apply(resource, in);
     }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/group/GetIncludedGroup.java b/gerrit-server/src/main/java/com/google/gerrit/server/group/GetSubgroup.java
similarity index 84%
rename from gerrit-server/src/main/java/com/google/gerrit/server/group/GetIncludedGroup.java
rename to gerrit-server/src/main/java/com/google/gerrit/server/group/GetSubgroup.java
index 4cf0cb2..a710188 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/group/GetIncludedGroup.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/group/GetSubgroup.java
@@ -21,16 +21,16 @@
 import com.google.inject.Singleton;
 
 @Singleton
-public class GetIncludedGroup implements RestReadView<IncludedGroupResource> {
+public class GetSubgroup implements RestReadView<SubgroupResource> {
   private final GroupJson json;
 
   @Inject
-  GetIncludedGroup(GroupJson json) {
+  GetSubgroup(GroupJson json) {
     this.json = json;
   }
 
   @Override
-  public GroupInfo apply(IncludedGroupResource rsrc) throws OrmException {
+  public GroupInfo apply(SubgroupResource rsrc) throws OrmException {
     return json.format(rsrc.getMemberDescription());
   }
 }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/group/GroupJson.java b/gerrit-server/src/main/java/com/google/gerrit/server/group/GroupJson.java
index 639ee55..85be5c4 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/group/GroupJson.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/group/GroupJson.java
@@ -45,7 +45,7 @@
   private final GroupBackend groupBackend;
   private final GroupControl.Factory groupControlFactory;
   private final Provider<ListMembers> listMembers;
-  private final Provider<ListIncludedGroups> listIncludes;
+  private final Provider<ListSubgroups> listSubgroups;
   private EnumSet<ListGroupsOption> options;
 
   @Inject
@@ -53,11 +53,11 @@
       GroupBackend groupBackend,
       GroupControl.Factory groupControlFactory,
       Provider<ListMembers> listMembers,
-      Provider<ListIncludedGroups> listIncludes) {
+      Provider<ListSubgroups> listSubgroups) {
     this.groupBackend = groupBackend;
     this.groupControlFactory = groupControlFactory;
     this.listMembers = listMembers;
-    this.listIncludes = listIncludes;
+    this.listSubgroups = listSubgroups;
 
     options = EnumSet.noneOf(ListGroupsOption.class);
   }
@@ -74,7 +74,7 @@
 
   public GroupInfo format(GroupResource rsrc) throws OrmException {
     GroupInfo info = init(rsrc.getGroup());
-    initMembersAndIncludes(rsrc, info);
+    initMembersAndSubgroups(rsrc, info);
     return info;
   }
 
@@ -82,7 +82,7 @@
     GroupInfo info = init(group);
     if (options.contains(MEMBERS) || options.contains(INCLUDES)) {
       GroupResource rsrc = new GroupResource(groupControlFactory.controlFor(group));
-      initMembersAndIncludes(rsrc, info);
+      initMembersAndSubgroups(rsrc, info);
     }
     return info;
   }
@@ -116,7 +116,8 @@
     return group instanceof GroupDescription.Internal;
   }
 
-  private GroupInfo initMembersAndIncludes(GroupResource rsrc, GroupInfo info) throws OrmException {
+  private GroupInfo initMembersAndSubgroups(GroupResource rsrc, GroupInfo info)
+      throws OrmException {
     if (!rsrc.isInternalGroup()) {
       return info;
     }
@@ -126,7 +127,7 @@
       }
 
       if (options.contains(INCLUDES)) {
-        info.includes = listIncludes.get().apply(rsrc);
+        info.includes = listSubgroups.get().apply(rsrc);
       }
       return info;
     } catch (MethodNotAllowedException e) {
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/group/Groups.java b/gerrit-server/src/main/java/com/google/gerrit/server/group/Groups.java
index 9f840ee..b835d22 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/group/Groups.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/group/Groups.java
@@ -145,16 +145,16 @@
    *
    * @param db the {@code ReviewDb} instance to use for lookups
    * @param parentGroupUuid the UUID of the parent group
-   * @param includedGroupUuid the UUID of the subgroup
+   * @param subgroupUuid the UUID of the subgroup
    * @return {@code true} if the group is a subgroup of the other group, or else {@code false}
    * @throws OrmException if an error occurs while reading from ReviewDb
    * @throws NoSuchGroupException if the specified parent group doesn't exist
    */
-  public boolean isIncluded(
-      ReviewDb db, AccountGroup.UUID parentGroupUuid, AccountGroup.UUID includedGroupUuid)
+  public boolean isSubgroup(
+      ReviewDb db, AccountGroup.UUID parentGroupUuid, AccountGroup.UUID subgroupUuid)
       throws OrmException, NoSuchGroupException {
     AccountGroup parentGroup = getExistingGroup(db, parentGroupUuid);
-    AccountGroupById.Key key = new AccountGroupById.Key(parentGroup.getId(), includedGroupUuid);
+    AccountGroupById.Key key = new AccountGroupById.Key(parentGroup.getId(), subgroupUuid);
     return db.accountGroupById().get(key) != null;
   }
 
@@ -191,7 +191,7 @@
    * @throws OrmException if an error occurs while reading from ReviewDb
    * @throws NoSuchGroupException if the specified parent group doesn't exist
    */
-  public Stream<AccountGroup.UUID> getIncludes(ReviewDb db, AccountGroup.UUID groupUuid)
+  public Stream<AccountGroup.UUID> getSubgroups(ReviewDb db, AccountGroup.UUID groupUuid)
       throws OrmException, NoSuchGroupException {
     AccountGroup group = getExistingGroup(db, groupUuid);
     ResultSet<AccountGroupById> accountGroupByIds = db.accountGroupById().byGroup(group.getId());
@@ -226,14 +226,14 @@
    * exist. This method doesn't check whether the parent groups exist.
    *
    * @param db the {@code ReviewDb} instance to use for lookups
-   * @param includedGroupUuid the UUID of the subgroup
+   * @param subgroupUuid the UUID of the subgroup
    * @return a stream of the IDs of the parent groups
    * @throws OrmException if an error occurs while reading from ReviewDb
    */
-  public Stream<AccountGroup.Id> getParentGroups(ReviewDb db, AccountGroup.UUID includedGroupUuid)
+  public Stream<AccountGroup.Id> getParentGroups(ReviewDb db, AccountGroup.UUID subgroupUuid)
       throws OrmException {
     ResultSet<AccountGroupById> accountGroupByIds =
-        db.accountGroupById().byIncludeUUID(includedGroupUuid);
+        db.accountGroupById().byIncludeUUID(subgroupUuid);
     return Streams.stream(accountGroupByIds).map(AccountGroupById::getGroupId);
   }
 
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/group/GroupsUpdate.java b/gerrit-server/src/main/java/com/google/gerrit/server/group/GroupsUpdate.java
index a55850a..d688e4c 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/group/GroupsUpdate.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/group/GroupsUpdate.java
@@ -349,35 +349,35 @@
    *
    * @param db the {@code ReviewDb} instance to update
    * @param parentGroupUuid the UUID of the parent group
-   * @param includedGroupUuids a set of IDs of the groups to add as subgroups
+   * @param subgroupUuids a set of IDs of the groups to add as subgroups
    * @throws OrmException if an error occurs while reading/writing from/to ReviewDb
    * @throws IOException if the parent group couldn't be indexed
    * @throws NoSuchGroupException if the specified parent group doesn't exist
    */
-  public void addIncludedGroups(
-      ReviewDb db, AccountGroup.UUID parentGroupUuid, Set<AccountGroup.UUID> includedGroupUuids)
+  public void addSubgroups(
+      ReviewDb db, AccountGroup.UUID parentGroupUuid, Set<AccountGroup.UUID> subgroupUuids)
       throws OrmException, NoSuchGroupException, IOException {
     AccountGroup parentGroup = groups.getExistingGroup(db, parentGroupUuid);
     AccountGroup.Id parentGroupId = parentGroup.getId();
-    Set<AccountGroupById> newIncludedGroups = new HashSet<>();
-    for (AccountGroup.UUID includedGroupUuid : includedGroupUuids) {
-      boolean isIncluded = groups.isIncluded(db, parentGroupUuid, includedGroupUuid);
-      if (!isIncluded) {
+    Set<AccountGroupById> newSubgroups = new HashSet<>();
+    for (AccountGroup.UUID includedGroupUuid : subgroupUuids) {
+      boolean isSubgroup = groups.isSubgroup(db, parentGroupUuid, includedGroupUuid);
+      if (!isSubgroup) {
         AccountGroupById.Key key = new AccountGroupById.Key(parentGroupId, includedGroupUuid);
-        newIncludedGroups.add(new AccountGroupById(key));
+        newSubgroups.add(new AccountGroupById(key));
       }
     }
 
-    if (newIncludedGroups.isEmpty()) {
+    if (newSubgroups.isEmpty()) {
       return;
     }
 
     if (currentUser != null) {
-      auditService.dispatchAddGroupsToGroup(currentUser.getAccountId(), newIncludedGroups);
+      auditService.dispatchAddGroupsToGroup(currentUser.getAccountId(), newSubgroups);
     }
-    db.accountGroupById().insert(newIncludedGroups);
+    db.accountGroupById().insert(newSubgroups);
     groupCache.evict(parentGroup.getGroupUUID(), parentGroup.getId(), parentGroup.getNameKey());
-    for (AccountGroupById newIncludedGroup : newIncludedGroups) {
+    for (AccountGroupById newIncludedGroup : newSubgroups) {
       groupIncludeCache.evictParentGroupsOf(newIncludedGroup.getIncludeUUID());
     }
     groupIncludeCache.evictSubgroupsOf(parentGroupUuid);
@@ -392,36 +392,35 @@
    *
    * @param db the {@code ReviewDb} instance to update
    * @param parentGroupUuid the UUID of the parent group
-   * @param includedGroupUuids a set of IDs of the subgroups to remove from the parent group
+   * @param subgroupUuids a set of IDs of the subgroups to remove from the parent group
    * @throws OrmException if an error occurs while reading/writing from/to ReviewDb
    * @throws IOException if the parent group couldn't be indexed
    * @throws NoSuchGroupException if the specified parent group doesn't exist
    */
-  public void deleteIncludedGroups(
-      ReviewDb db, AccountGroup.UUID parentGroupUuid, Set<AccountGroup.UUID> includedGroupUuids)
+  public void removeSubgroups(
+      ReviewDb db, AccountGroup.UUID parentGroupUuid, Set<AccountGroup.UUID> subgroupUuids)
       throws OrmException, NoSuchGroupException, IOException {
     AccountGroup parentGroup = groups.getExistingGroup(db, parentGroupUuid);
     AccountGroup.Id parentGroupId = parentGroup.getId();
-    Set<AccountGroupById> includedGroupsToRemove = new HashSet<>();
-    for (AccountGroup.UUID includedGroupUuid : includedGroupUuids) {
-      boolean isIncluded = groups.isIncluded(db, parentGroupUuid, includedGroupUuid);
-      if (isIncluded) {
-        AccountGroupById.Key key = new AccountGroupById.Key(parentGroupId, includedGroupUuid);
-        includedGroupsToRemove.add(new AccountGroupById(key));
+    Set<AccountGroupById> subgroupsToRemove = new HashSet<>();
+    for (AccountGroup.UUID subgroupUuid : subgroupUuids) {
+      boolean isSubgroup = groups.isSubgroup(db, parentGroupUuid, subgroupUuid);
+      if (isSubgroup) {
+        AccountGroupById.Key key = new AccountGroupById.Key(parentGroupId, subgroupUuid);
+        subgroupsToRemove.add(new AccountGroupById(key));
       }
     }
 
-    if (includedGroupsToRemove.isEmpty()) {
+    if (subgroupsToRemove.isEmpty()) {
       return;
     }
 
     if (currentUser != null) {
-      auditService.dispatchDeleteGroupsFromGroup(
-          currentUser.getAccountId(), includedGroupsToRemove);
+      auditService.dispatchDeleteGroupsFromGroup(currentUser.getAccountId(), subgroupsToRemove);
     }
-    db.accountGroupById().delete(includedGroupsToRemove);
+    db.accountGroupById().delete(subgroupsToRemove);
     groupCache.evict(parentGroup.getGroupUUID(), parentGroup.getId(), parentGroup.getNameKey());
-    for (AccountGroupById groupToRemove : includedGroupsToRemove) {
+    for (AccountGroupById groupToRemove : subgroupsToRemove) {
       groupIncludeCache.evictParentGroupsOf(groupToRemove.getIncludeUUID());
     }
     groupIncludeCache.evictSubgroupsOf(parentGroupUuid);
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/group/InternalGroup.java b/gerrit-server/src/main/java/com/google/gerrit/server/group/InternalGroup.java
index 6863b36..228d86f 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/group/InternalGroup.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/group/InternalGroup.java
@@ -27,7 +27,7 @@
   public static InternalGroup create(
       AccountGroup accountGroup,
       ImmutableSet<Account.Id> members,
-      ImmutableSet<AccountGroup.UUID> includes) {
+      ImmutableSet<AccountGroup.UUID> subgroups) {
     return new AutoValue_InternalGroup(
         accountGroup.getId(),
         accountGroup.getNameKey(),
@@ -37,7 +37,7 @@
         accountGroup.getGroupUUID(),
         accountGroup.getCreatedOn(),
         members,
-        includes);
+        subgroups);
   }
 
   public abstract AccountGroup.Id getId();
@@ -61,5 +61,5 @@
 
   public abstract ImmutableSet<Account.Id> getMembers();
 
-  public abstract ImmutableSet<AccountGroup.UUID> getIncludes();
+  public abstract ImmutableSet<AccountGroup.UUID> getSubgroups();
 }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/group/ListMembers.java b/gerrit-server/src/main/java/com/google/gerrit/server/group/ListMembers.java
index b92962b..af988b8 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/group/ListMembers.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/group/ListMembers.java
@@ -96,7 +96,7 @@
 
     Set<Account.Id> indirectMembers = new HashSet<>();
     if (recursive && groupControl.canSeeGroup()) {
-      for (AccountGroup.UUID subgroupUuid : group.getIncludes()) {
+      for (AccountGroup.UUID subgroupUuid : group.getSubgroups()) {
         if (!seenGroups.contains(subgroupUuid)) {
           indirectMembers.addAll(getMembers(subgroupUuid, seenGroups));
         }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/group/ListIncludedGroups.java b/gerrit-server/src/main/java/com/google/gerrit/server/group/ListSubgroups.java
similarity index 86%
rename from gerrit-server/src/main/java/com/google/gerrit/server/group/ListIncludedGroups.java
rename to gerrit-server/src/main/java/com/google/gerrit/server/group/ListSubgroups.java
index 33d9b57..2000d66 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/group/ListIncludedGroups.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/group/ListSubgroups.java
@@ -35,15 +35,15 @@
 import org.slf4j.Logger;
 
 @Singleton
-public class ListIncludedGroups implements RestReadView<GroupResource> {
-  private static final Logger log = org.slf4j.LoggerFactory.getLogger(ListIncludedGroups.class);
+public class ListSubgroups implements RestReadView<GroupResource> {
+  private static final Logger log = org.slf4j.LoggerFactory.getLogger(ListSubgroups.class);
 
   private final GroupControl.Factory controlFactory;
   private final GroupIncludeCache groupIncludeCache;
   private final GroupJson json;
 
   @Inject
-  ListIncludedGroups(
+  ListSubgroups(
       GroupControl.Factory controlFactory, GroupIncludeCache groupIncludeCache, GroupJson json) {
     this.controlFactory = controlFactory;
     this.groupIncludeCache = groupIncludeCache;
@@ -57,19 +57,18 @@
 
     boolean ownerOfParent = rsrc.getControl().isOwner();
     List<GroupInfo> included = new ArrayList<>();
-    Collection<AccountGroup.UUID> includedGroupUuids =
+    Collection<AccountGroup.UUID> subgroupUuids =
         groupIncludeCache.subgroupsOf(group.getGroupUUID());
-    for (AccountGroup.UUID includedGroupUuid : includedGroupUuids) {
+    for (AccountGroup.UUID subgroupUuid : subgroupUuids) {
       try {
-        GroupControl i = controlFactory.controlFor(includedGroupUuid);
+        GroupControl i = controlFactory.controlFor(subgroupUuid);
         if (ownerOfParent || i.isVisible()) {
           included.add(json.format(i.getGroup()));
         }
       } catch (NoSuchGroupException notFound) {
         log.warn(
             String.format(
-                "Group %s no longer available, included into %s",
-                includedGroupUuid, group.getName()));
+                "Group %s no longer available, subgroup of %s", subgroupUuid, group.getName()));
         continue;
       }
     }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/group/Module.java b/gerrit-server/src/main/java/com/google/gerrit/server/group/Module.java
index ef70484..5006914 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/group/Module.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/group/Module.java
@@ -15,18 +15,18 @@
 package com.google.gerrit.server.group;
 
 import static com.google.gerrit.server.group.GroupResource.GROUP_KIND;
-import static com.google.gerrit.server.group.IncludedGroupResource.INCLUDED_GROUP_KIND;
 import static com.google.gerrit.server.group.MemberResource.MEMBER_KIND;
+import static com.google.gerrit.server.group.SubgroupResource.SUBGROUP_KIND;
 
 import com.google.gerrit.audit.GroupMemberAuditListener;
 import com.google.gerrit.extensions.registration.DynamicMap;
 import com.google.gerrit.extensions.registration.DynamicSet;
 import com.google.gerrit.extensions.restapi.RestApiModule;
 import com.google.gerrit.server.IdentifiedUser;
-import com.google.gerrit.server.group.AddIncludedGroups.UpdateIncludedGroup;
 import com.google.gerrit.server.group.AddMembers.UpdateMember;
-import com.google.gerrit.server.group.DeleteIncludedGroups.DeleteIncludedGroup;
+import com.google.gerrit.server.group.AddSubgroups.UpdateSubgroup;
 import com.google.gerrit.server.group.DeleteMembers.DeleteMember;
+import com.google.gerrit.server.group.DeleteSubgroups.DeleteSubgroup;
 import com.google.inject.Provides;
 
 public class Module extends RestApiModule {
@@ -36,7 +36,7 @@
 
     DynamicMap.mapOf(binder(), GROUP_KIND);
     DynamicMap.mapOf(binder(), MEMBER_KIND);
-    DynamicMap.mapOf(binder(), INCLUDED_GROUP_KIND);
+    DynamicMap.mapOf(binder(), SUBGROUP_KIND);
 
     get(GROUP_KIND).to(GetGroup.class);
     put(GROUP_KIND).to(PutGroup.class);
@@ -45,9 +45,9 @@
     post(GROUP_KIND, "members").to(AddMembers.class);
     post(GROUP_KIND, "members.add").to(AddMembers.class);
     post(GROUP_KIND, "members.delete").to(DeleteMembers.class);
-    post(GROUP_KIND, "groups").to(AddIncludedGroups.class);
-    post(GROUP_KIND, "groups.add").to(AddIncludedGroups.class);
-    post(GROUP_KIND, "groups.delete").to(DeleteIncludedGroups.class);
+    post(GROUP_KIND, "groups").to(AddSubgroups.class);
+    post(GROUP_KIND, "groups.add").to(AddSubgroups.class);
+    post(GROUP_KIND, "groups.delete").to(DeleteSubgroups.class);
     get(GROUP_KIND, "description").to(GetDescription.class);
     put(GROUP_KIND, "description").to(PutDescription.class);
     delete(GROUP_KIND, "description").to(PutDescription.class);
@@ -64,10 +64,10 @@
     put(MEMBER_KIND).to(UpdateMember.class);
     delete(MEMBER_KIND).to(DeleteMember.class);
 
-    child(GROUP_KIND, "groups").to(IncludedGroupsCollection.class);
-    get(INCLUDED_GROUP_KIND).to(GetIncludedGroup.class);
-    put(INCLUDED_GROUP_KIND).to(UpdateIncludedGroup.class);
-    delete(INCLUDED_GROUP_KIND).to(DeleteIncludedGroup.class);
+    child(GROUP_KIND, "groups").to(SubgroupsCollection.class);
+    get(SUBGROUP_KIND).to(GetSubgroup.class);
+    put(SUBGROUP_KIND).to(UpdateSubgroup.class);
+    delete(SUBGROUP_KIND).to(DeleteSubgroup.class);
 
     factory(CreateGroup.Factory.class);
     factory(GroupsUpdate.Factory.class);
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/group/IncludedGroupResource.java b/gerrit-server/src/main/java/com/google/gerrit/server/group/SubgroupResource.java
similarity index 79%
rename from gerrit-server/src/main/java/com/google/gerrit/server/group/IncludedGroupResource.java
rename to gerrit-server/src/main/java/com/google/gerrit/server/group/SubgroupResource.java
index 467de4c..50c769d 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/group/IncludedGroupResource.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/group/SubgroupResource.java
@@ -19,13 +19,13 @@
 import com.google.gerrit.reviewdb.client.AccountGroup;
 import com.google.inject.TypeLiteral;
 
-public class IncludedGroupResource extends GroupResource {
-  public static final TypeLiteral<RestView<IncludedGroupResource>> INCLUDED_GROUP_KIND =
-      new TypeLiteral<RestView<IncludedGroupResource>>() {};
+public class SubgroupResource extends GroupResource {
+  public static final TypeLiteral<RestView<SubgroupResource>> SUBGROUP_KIND =
+      new TypeLiteral<RestView<SubgroupResource>>() {};
 
   private final GroupDescription.Basic member;
 
-  public IncludedGroupResource(GroupResource group, GroupDescription.Basic member) {
+  public SubgroupResource(GroupResource group, GroupDescription.Basic member) {
     super(group);
     this.member = member;
   }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/group/IncludedGroupsCollection.java b/gerrit-server/src/main/java/com/google/gerrit/server/group/SubgroupsCollection.java
similarity index 72%
rename from gerrit-server/src/main/java/com/google/gerrit/server/group/IncludedGroupsCollection.java
rename to gerrit-server/src/main/java/com/google/gerrit/server/group/SubgroupsCollection.java
index d48acee..e2aacd6 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/group/IncludedGroupsCollection.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/group/SubgroupsCollection.java
@@ -26,36 +26,36 @@
 import com.google.gerrit.extensions.restapi.RestView;
 import com.google.gerrit.extensions.restapi.TopLevelResource;
 import com.google.gerrit.reviewdb.server.ReviewDb;
-import com.google.gerrit.server.group.AddIncludedGroups.PutIncludedGroup;
+import com.google.gerrit.server.group.AddSubgroups.PutSubgroup;
 import com.google.gwtorm.server.OrmException;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
 import com.google.inject.Singleton;
 
 @Singleton
-public class IncludedGroupsCollection
-    implements ChildCollection<GroupResource, IncludedGroupResource>, AcceptsCreate<GroupResource> {
-  private final DynamicMap<RestView<IncludedGroupResource>> views;
-  private final ListIncludedGroups list;
+public class SubgroupsCollection
+    implements ChildCollection<GroupResource, SubgroupResource>, AcceptsCreate<GroupResource> {
+  private final DynamicMap<RestView<SubgroupResource>> views;
+  private final ListSubgroups list;
   private final GroupsCollection groupsCollection;
   private final Provider<ReviewDb> dbProvider;
   private final Groups groups;
-  private final AddIncludedGroups put;
+  private final AddSubgroups addSubgroups;
 
   @Inject
-  IncludedGroupsCollection(
-      DynamicMap<RestView<IncludedGroupResource>> views,
-      ListIncludedGroups list,
+  SubgroupsCollection(
+      DynamicMap<RestView<SubgroupResource>> views,
+      ListSubgroups list,
       GroupsCollection groupsCollection,
       Provider<ReviewDb> dbProvider,
       Groups groups,
-      AddIncludedGroups put) {
+      AddSubgroups addSubgroups) {
     this.views = views;
     this.list = list;
     this.groupsCollection = groupsCollection;
     this.dbProvider = dbProvider;
     this.groups = groups;
-    this.put = put;
+    this.addSubgroups = addSubgroups;
   }
 
   @Override
@@ -64,23 +64,23 @@
   }
 
   @Override
-  public IncludedGroupResource parse(GroupResource resource, IdString id)
+  public SubgroupResource parse(GroupResource resource, IdString id)
       throws MethodNotAllowedException, AuthException, ResourceNotFoundException, OrmException {
     GroupDescription.Internal parent =
         resource.asInternalGroup().orElseThrow(MethodNotAllowedException::new);
 
     GroupDescription.Basic member =
         groupsCollection.parse(TopLevelResource.INSTANCE, id).getGroup();
-    if (resource.getControl().canSeeGroup() && isMember(parent, member)) {
-      return new IncludedGroupResource(resource, member);
+    if (resource.getControl().canSeeGroup() && isSubgroup(parent, member)) {
+      return new SubgroupResource(resource, member);
     }
     throw new ResourceNotFoundException(id);
   }
 
-  private boolean isMember(GroupDescription.Internal parent, GroupDescription.Basic member)
+  private boolean isSubgroup(GroupDescription.Internal parent, GroupDescription.Basic member)
       throws OrmException, ResourceNotFoundException {
     try {
-      return groups.isIncluded(dbProvider.get(), parent.getGroupUUID(), member.getGroupUUID());
+      return groups.isSubgroup(dbProvider.get(), parent.getGroupUUID(), member.getGroupUUID());
     } catch (NoSuchGroupException e) {
       throw new ResourceNotFoundException(
           String.format("Group %s not found", parent.getGroupUUID()));
@@ -89,12 +89,12 @@
 
   @SuppressWarnings("unchecked")
   @Override
-  public PutIncludedGroup create(GroupResource group, IdString id) {
-    return new PutIncludedGroup(put, id.get());
+  public PutSubgroup create(GroupResource group, IdString id) {
+    return new PutSubgroup(addSubgroups, id.get());
   }
 
   @Override
-  public DynamicMap<RestView<IncludedGroupResource>> views() {
+  public DynamicMap<RestView<SubgroupResource>> views() {
     return views;
   }
 }
diff --git a/gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/CreateGroupCommand.java b/gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/CreateGroupCommand.java
index 5a8e4bb..6b5d632 100644
--- a/gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/CreateGroupCommand.java
+++ b/gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/CreateGroupCommand.java
@@ -25,8 +25,8 @@
 import com.google.gerrit.extensions.restapi.TopLevelResource;
 import com.google.gerrit.reviewdb.client.Account;
 import com.google.gerrit.reviewdb.client.AccountGroup;
-import com.google.gerrit.server.group.AddIncludedGroups;
 import com.google.gerrit.server.group.AddMembers;
+import com.google.gerrit.server.group.AddSubgroups;
 import com.google.gerrit.server.group.CreateGroup;
 import com.google.gerrit.server.group.GroupResource;
 import com.google.gerrit.server.group.GroupsCollection;
@@ -101,7 +101,7 @@
 
   @Inject private AddMembers addMembers;
 
-  @Inject private AddIncludedGroups addIncludedGroups;
+  @Inject private AddSubgroups addSubgroups;
 
   @Override
   protected void run() throws Failure, OrmException, IOException, ConfigInvalidException {
@@ -113,7 +113,7 @@
       }
 
       if (!initialGroups.isEmpty()) {
-        addIncludedGroups(rsrc);
+        addSubgroups(rsrc);
       }
     } catch (RestApiException e) {
       throw die(e);
@@ -142,11 +142,10 @@
     addMembers.apply(rsrc, input);
   }
 
-  private void addIncludedGroups(GroupResource rsrc)
-      throws RestApiException, OrmException, IOException {
-    AddIncludedGroups.Input input =
-        AddIncludedGroups.Input.fromGroups(
+  private void addSubgroups(GroupResource rsrc) throws RestApiException, OrmException, IOException {
+    AddSubgroups.Input input =
+        AddSubgroups.Input.fromGroups(
             initialGroups.stream().map(AccountGroup.UUID::get).collect(toList()));
-    addIncludedGroups.apply(rsrc, input);
+    addSubgroups.apply(rsrc, input);
   }
 }
diff --git a/gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/SetMembersCommand.java b/gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/SetMembersCommand.java
index a5ebaeb..9062b52 100644
--- a/gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/SetMembersCommand.java
+++ b/gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/SetMembersCommand.java
@@ -26,10 +26,10 @@
 import com.google.gerrit.reviewdb.client.AccountGroup;
 import com.google.gerrit.server.account.AccountCache;
 import com.google.gerrit.server.account.GroupCache;
-import com.google.gerrit.server.group.AddIncludedGroups;
 import com.google.gerrit.server.group.AddMembers;
-import com.google.gerrit.server.group.DeleteIncludedGroups;
+import com.google.gerrit.server.group.AddSubgroups;
 import com.google.gerrit.server.group.DeleteMembers;
+import com.google.gerrit.server.group.DeleteSubgroups;
 import com.google.gerrit.server.group.GroupResource;
 import com.google.gerrit.server.group.GroupsCollection;
 import com.google.gerrit.server.group.InternalGroup;
@@ -94,9 +94,9 @@
 
   @Inject private DeleteMembers deleteMembers;
 
-  @Inject private AddIncludedGroups addIncludedGroups;
+  @Inject private AddSubgroups addSubgroups;
 
-  @Inject private DeleteIncludedGroups deleteIncludedGroups;
+  @Inject private DeleteSubgroups deleteSubgroups;
 
   @Inject private GroupsCollection groupsCollection;
 
@@ -115,7 +115,7 @@
           reportMembersAction("removed from", resource, accountsToRemove);
         }
         if (!groupsToRemove.isEmpty()) {
-          deleteIncludedGroups.apply(resource, fromGroups(groupsToRemove));
+          deleteSubgroups.apply(resource, fromGroups(groupsToRemove));
           reportGroupsAction("excluded from", resource, groupsToRemove);
         }
         if (!accountsToAdd.isEmpty()) {
@@ -123,7 +123,7 @@
           reportMembersAction("added to", resource, accountsToAdd);
         }
         if (!groupsToInclude.isEmpty()) {
-          addIncludedGroups.apply(resource, fromGroups(groupsToInclude));
+          addSubgroups.apply(resource, fromGroups(groupsToInclude));
           reportGroupsAction("included to", resource, groupsToInclude);
         }
       }
@@ -160,9 +160,8 @@
         String.format("Groups %s group %s: %s\n", action, group.getName(), names).getBytes(ENC));
   }
 
-  private AddIncludedGroups.Input fromGroups(List<AccountGroup.UUID> accounts) {
-    return AddIncludedGroups.Input.fromGroups(
-        accounts.stream().map(Object::toString).collect(toList()));
+  private AddSubgroups.Input fromGroups(List<AccountGroup.UUID> accounts) {
+    return AddSubgroups.Input.fromGroups(accounts.stream().map(Object::toString).collect(toList()));
   }
 
   private AddMembers.Input fromMembers(List<Account.Id> accounts) {