Effect: Fix typo

Closes gh-1778

Author: lukeb

ui/effect.js

@@ -1359,7 +1359,7 @@ $.fn.extend( {
 				var el = $( this ),
 					normalizedMode = $.effects.mode( el, mode ) || defaultMode;
 
-				// Sentinel for duck-punching the :animated psuedo-selector
+				// Sentinel for duck-punching the :animated pseudo-selector
 				el.data( dataSpaceAnimated, true );
 
 				// Save effect mode for later use,