diff --git a/Library/Homebrew/cask/cask.rb b/Library/Homebrew/cask/cask.rb
index e3d6d51041..8c0870c4ec 100644
--- a/Library/Homebrew/cask/cask.rb
+++ b/Library/Homebrew/cask/cask.rb
@@ -87,7 +87,7 @@ module Cask
     sig { returns(T::Array[String]) }
     def old_tokens
       @old_tokens ||= if (tap = self.tap)
-        Tap.reverse_tap_migrations_renames(tap, token) +
+        Tap.tap_migration_oldnames(tap, token) +
           tap.cask_reverse_renames.fetch(token, [])
       else
         []
diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index d9394808b1..285f05a7c6 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -552,7 +552,7 @@ class Formula
   sig { returns(T::Array[String]) }
   def oldnames
     @oldnames ||= if (tap = self.tap)
-      Tap.reverse_tap_migrations_renames(tap, name) +
+      Tap.tap_migration_oldnames(tap, name) +
         tap.formula_reverse_renames.fetch(name, [])
     else
       []
diff --git a/Library/Homebrew/tap.rb b/Library/Homebrew/tap.rb
index 27a93283aa..e38060f3b8 100644
--- a/Library/Homebrew/tap.rb
+++ b/Library/Homebrew/tap.rb
@@ -867,6 +867,9 @@ class Tap
   sig { returns(T::Hash[String, T::Array[String]]) }
   def reverse_tap_migrations_renames
     @reverse_tap_migrations_renames ||= tap_migrations.each_with_object({}) do |(old_name, new_name), hash|
+      # Only include renames:
+      # + `homebrew/cask/water-buffalo`
+      # - `homebrew/cask`
       next if new_name.count("/") != 2
 
       hash[new_name] ||= []
@@ -874,9 +877,10 @@ class Tap
     end
   end
 
-  sig { params(new_tap: Tap, name_or_token: String).returns(T::Array[String]) }
-  def self.reverse_tap_migrations_renames(new_tap, name_or_token)
-    key = "#{new_tap}/#{name_or_token}"
+  # The old names a formula or cask had before getting migrated to the current tap.
+  sig { params(current_tap: Tap, name_or_token: String).returns(T::Array[String]) }
+  def self.tap_migration_oldnames(current_tap, name_or_token)
+    key = "#{current_tap}/#{name_or_token}"
 
     Tap.each_with_object([]) do |tap, array|
       next unless (renames = tap.reverse_tap_migrations_renames[key])
diff --git a/Library/Homebrew/test/api/internal_tap_json/formula_spec.rb b/Library/Homebrew/test/api/internal_tap_json/formula_spec.rb
index fe5ebf47a9..1426677483 100644
--- a/Library/Homebrew/test/api/internal_tap_json/formula_spec.rb
+++ b/Library/Homebrew/test/api/internal_tap_json/formula_spec.rb
@@ -33,7 +33,7 @@ RSpec.describe "Internal Tap JSON -- Formula" do
         .with("internal/v3/homebrew-core.jws.json")
         .and_return([JSON.parse(internal_tap_json), false])
 
-      # `Tap.reverse_tap_migrations_renames` looks for renames in every
+      # `Tap.tap_migration_oldnames` looks for renames in every
       # tap so `CoreCaskTap.tap_migrations` gets called and tries to
       # fetch stuff from the API. This just avoids errors.
       allow(Homebrew::API).to receive(:fetch_json_api_file)
diff --git a/Library/Homebrew/test/tap_spec.rb b/Library/Homebrew/test/tap_spec.rb
index bd43008b9c..0c2d110b3d 100644
--- a/Library/Homebrew/test/tap_spec.rb
+++ b/Library/Homebrew/test/tap_spec.rb
@@ -586,7 +586,7 @@ RSpec.describe Tap do
         end
       end
 
-      describe ".reverse_tap_migration_renames" do
+      describe ".tap_migration_oldnames" do
         let(:cask_tap) { CoreCaskTap.instance }
         let(:core_tap) { CoreTap.instance }
 
@@ -597,7 +597,7 @@ RSpec.describe Tap do
             [cask_tap, "schism-tracker", %w[schismtracker]],
             [cask_tap, "google-cloud-sdk", %w[app-engine-go-32 app-engine-go-64]],
           ].each do |tap, name, result|
-            expect(described_class.reverse_tap_migrations_renames(tap, name)).to eq(result)
+            expect(described_class.tap_migration_oldnames(tap, name)).to eq(result)
           end
         end
       end