diff --git a/underscore.js b/underscore.js
index c8cd1fd0e..0d078a6a7 100644
--- a/underscore.js
+++ b/underscore.js
@@ -48,21 +48,16 @@
   // Create a safe reference to the Underscore object for use below.
   var _ = function(obj) { return new wrapper(obj); };
 
-  // Export the Underscore object for **Node.js** and **"CommonJS"**, with
-  // backwards-compatibility for the old `require()` API. If we're not in
-  // CommonJS, add `_` to the global object.
+  // Export the Underscore object for **Node.js**, with
+  // backwards-compatibility for the old `require()` API. If we're in
+  // the browser, add `_` as a global object via a string identifier,
+  // for Closure Compiler "advanced" mode.
   if (typeof exports !== 'undefined') {
     if (typeof module !== 'undefined' && module.exports) {
       exports = module.exports = _;
     }
     exports._ = _;
-  } else if (typeof define === 'function' && define.amd) {
-    // Register as a named module with AMD.
-    define('underscore', function() {
-      return _;
-    });
   } else {
-    // Exported as a string, for Closure Compiler "advanced" mode.
     root['_'] = _;
   }