diff --git a/spacy/errors.py b/spacy/errors.py
index 51a10be17..92770b8a8 100644
--- a/spacy/errors.py
+++ b/spacy/errors.py
@@ -82,7 +82,7 @@ class Warnings(metaclass=ErrorsWithCodes):
             "ignoring the duplicate entry.")
     W021 = ("Unexpected hash collision in PhraseMatcher. Matches may be "
             "incorrect. Modify PhraseMatcher._terminal_hash to fix.")
-    W024 = ("Entity '{entity}' - Alias '{alias}' combination already exists in "
+    W024 = ("Entity '{entity}' - mention '{mention}' combination already exists in "
             "the Knowledge Base.")
     W026 = ("Unable to set all sentence boundaries from dependency parses. If "
             "you are constructing a parse tree incrementally by setting "
diff --git a/spacy/kb/kb.pyx b/spacy/kb/kb.pyx
index ce4bc0138..158c3304f 100644
--- a/spacy/kb/kb.pyx
+++ b/spacy/kb/kb.pyx
@@ -11,7 +11,7 @@ from ..errors import Errors
 
 
 cdef class KnowledgeBase:
-    """A `KnowledgeBase` instance stores unique identifiers for entities and their textual aliases,
+    """A `KnowledgeBase` instance stores unique identifiers for entities and their textual mentions,
     to support entity linking of named entities to real-world concepts.
     This is an abstract class and requires its operations to be implemented.
 
@@ -32,8 +32,8 @@ cdef class KnowledgeBase:
 
     def get_candidates_batch(self, mentions: Iterable[Span]) -> Iterable[Iterable[Candidate]]:
         """
-        Return candidate entities for specified texts. Each candidate defines the entity, the original alias,
-        and the prior probability of that alias resolving to that entity.
+        Return candidate entities for specified texts. Each candidate defines the entity, the original mention,
+        and the prior probability of this mention resolving to that entity.
         If no candidate is found for a given text, an empty list is returned.
         mentions (Iterable[Span]): Mentions for which to get candidates.
         RETURNS (Iterable[Iterable[Candidate]]): Identified candidates.
@@ -42,8 +42,8 @@ cdef class KnowledgeBase:
 
     def get_candidates(self, mention: Span) -> Iterable[Candidate]:
         """
-        Return candidate entities for specified text. Each candidate defines the entity, the original alias,
-        and the prior probability of that alias resolving to that entity.
+        Return candidate entities for specified text. Each candidate defines the entity, the original mention,
+        and the prior probability of that mention resolving to that entity.
         If the no candidate is found for a given text, an empty list is returned.
         mention (Span): Mention for which to get candidates.
         RETURNS (Iterable[Candidate]): Identified candidates.
diff --git a/spacy/kb/kb_in_memory.pyx b/spacy/kb/kb_in_memory.pyx
index d456f729b..692390f10 100644
--- a/spacy/kb/kb_in_memory.pyx
+++ b/spacy/kb/kb_in_memory.pyx
@@ -22,7 +22,7 @@ from .candidate import InMemoryCandidate
 
 
 cdef class InMemoryLookupKB(KnowledgeBase):
-    """An `InMemoryLookupKB` instance stores unique identifiers for entities and their textual aliases,
+    """An `InMemoryLookupKB` instance stores unique identifiers for entities and their textual mentions,
     to support entity linking of named entities to real-world concepts.
 
     DOCS: https://spacy.io/api/inmemorylookupkb
@@ -216,7 +216,7 @@ cdef class InMemoryLookupKB(KnowledgeBase):
 
         if is_present:
             if not ignore_warnings:
-                warnings.warn(Warnings.W024.format(entity=entity, alias=alias))
+                warnings.warn(Warnings.W024.format(entity=entity, mention=alias))
         else:
             entry_indices.push_back(int(entry_index))
             alias_entry.entry_indices = entry_indices