diff --git a/src/core.js b/src/core.js
index e75c86fa..4da1212c 100644
--- a/src/core.js
+++ b/src/core.js
@@ -887,7 +887,7 @@ function doScrollCheck() {
 }
 
 // Expose jQuery as an Asynchronous Module
-if ( typeof define !== "undefined" ) {
+if ( typeof define === "function" ) {
 	define( "jquery", [], function () { return jQuery; } );
 }