diff --git a/src/lib/es5.d.ts b/src/lib/es5.d.ts
index f8715e493735a..b10358a0f7e9d 100644
--- a/src/lib/es5.d.ts
+++ b/src/lib/es5.d.ts
@@ -196,13 +196,13 @@ interface ObjectConstructor {
 
     /**
      * Prevents the modification of existing property attributes and values, and prevents the addition of new properties.
-     * @param o Object on which to lock the attributes.
+     * @param a Object on which to lock the attributes.
      */
     freeze<T>(a: T[]): readonly T[];
 
     /**
      * Prevents the modification of existing property attributes and values, and prevents the addition of new properties.
-     * @param o Object on which to lock the attributes.
+     * @param f Object on which to lock the attributes.
      */
     freeze<T extends Function>(f: T): T;