diff --git a/extensions/functions_boolean.yaml b/extensions/functions_boolean.yaml
index d899adf74..cd0629a09 100644
--- a/extensions/functions_boolean.yaml
+++ b/extensions/functions_boolean.yaml
@@ -1,14 +1,6 @@
 %YAML 1.2
 ---
 scalar_functions:
-  -
-    name: not
-    description: The boolean not of a provided value.
-    impls:
-      - args:
-          - value: boolean
-          - value: boolean
-        return: boolean
   -
     name: or
     description: The boolean or of two values using Kleene logic.