diff --git a/types/chai/chai-tests.ts b/types/chai/chai-tests.ts
index 75c3e09d15..3ae67aed20 100644
--- a/types/chai/chai-tests.ts
+++ b/types/chai/chai-tests.ts
@@ -1694,15 +1694,15 @@ suite('assert', () => {
         assert.deepProperty(obj, 'foo.bar');
         assert.notDeepProperty(obj, 'foo.baz');
         assert.deepPropertyVal(obj, 'foo.bar', 'baz');
-        assert.deepPropertyNotVal(simpleObj, 'foo.bar', 'flow');
+        assert.notDeepPropertyVal(simpleObj, 'foo.bar', 'flow');
         assert.property(simpleObj, 'baz');
         assert.deepProperty(obj, 'foo.baz');
         assert.notProperty(obj, 'foo');
         assert.notDeepProperty(obj, 'foo.bar');
         assert.propertyVal(simpleObj, 'foo', 'ball');
         assert.deepPropertyVal(obj, 'foo.bar', 'ball');
-        assert.propertyNotVal(simpleObj, 'foo', 'bar');
-        assert.deepPropertyNotVal(simpleObj, 'foo.bar', 'baz');
+        assert.notPropertyVal(simpleObj, 'foo', 'bar');
+        assert.notDeepPropertyVal(simpleObj, 'foo.bar', 'baz');
     });
 
     test('throws', () => {
diff --git a/types/chai/index.d.ts b/types/chai/index.d.ts
index 87da2a3092..ce3cb8c308 100644
--- a/types/chai/index.d.ts
+++ b/types/chai/index.d.ts
@@ -1126,7 +1126,7 @@ declare namespace Chai {
          * @param value   Potential expected property value.
          * @param message   Message to display on error.
          */
-        propertyNotVal<T, V>(object: T, property: string /* keyof T */, value: V, message?: string): void;
+        notPropertyVal<T, V>(object: T, property: string /* keyof T */, value: V, message?: string): void;
 
         /**
          * Asserts that object has a property named by property, which can be a string
@@ -1152,7 +1152,7 @@ declare namespace Chai {
          * @param value   Potential expected property value.
          * @param message   Message to display on error.
          */
-        deepPropertyNotVal<T, V>(object: T, property: string, value: V, message?: string): void;
+        notDeepPropertyVal<T, V>(object: T, property: string, value: V, message?: string): void;
 
         /**
          * Asserts that object has a length property with the expected value.