diff --git a/src/wp-admin/js/common.js b/src/wp-admin/js/common.js
index 6f66aeec8f..9fa67e5b65 100644
--- a/src/wp-admin/js/common.js
+++ b/src/wp-admin/js/common.js
@@ -83,7 +83,7 @@ validateForm = function( form ) {
 		.addClass( 'form-invalid' )
 		.find( 'input:visible' )
 		.change( function() { $( this ).closest( '.form-invalid' ).removeClass( 'form-invalid' ); } )
-		.size();
+		.length;
 };
 
 // stub for doing better warnings
diff --git a/src/wp-admin/js/edit-comments.js b/src/wp-admin/js/edit-comments.js
index 7fc62deb73..dd3025f194 100644
--- a/src/wp-admin/js/edit-comments.js
+++ b/src/wp-admin/js/edit-comments.js
@@ -481,7 +481,7 @@ setCommentsList = function() {
 			}
 		}
 
-		if ( ! theExtraList || theExtraList.size() === 0 || theExtraList.children().size() === 0 ) {
+		if ( ! theExtraList || theExtraList.length === 0 || theExtraList.children().length === 0 ) {
 			return;
 		}
 
diff --git a/src/wp-admin/js/media-upload.js b/src/wp-admin/js/media-upload.js
index 011b618ff5..cd969b9b3a 100644
--- a/src/wp-admin/js/media-upload.js
+++ b/src/wp-admin/js/media-upload.js
@@ -47,7 +47,7 @@ var tb_position;
 			adminbar_height = parseInt( $('#wpadminbar').css('height'), 10 );
 		}
 
-		if ( tbWindow.size() ) {
+		if ( tbWindow.length ) {
 			tbWindow.width( W - 50 ).height( H - 45 - adminbar_height );
 			$('#TB_iframeContent').width( W - 50 ).height( H - 75 - adminbar_height );
 			tbWindow.css({'margin-left': '-' + parseInt( ( ( W - 50 ) / 2 ), 10 ) + 'px'});
diff --git a/src/wp-admin/js/plugin-install.js b/src/wp-admin/js/plugin-install.js
index e9186cde1c..6693598e17 100644
--- a/src/wp-admin/js/plugin-install.js
+++ b/src/wp-admin/js/plugin-install.js
@@ -9,7 +9,7 @@ jQuery( document ).ready( function( $ ) {
 			H = $( window ).height() - ( ( 792 < width ) ? 60 : 20 ),
 			W = ( 792 < width ) ? 772 : width - 20;
 
-		if ( tbWindow.size() ) {
+		if ( tbWindow.length ) {
 			tbWindow.width( W ).height( H );
 			$( '#TB_iframeContent' ).width( W ).height( H );
 			tbWindow.css({
diff --git a/src/wp-admin/js/post.js b/src/wp-admin/js/post.js
index ae5e097cf6..0d7bf0359c 100644
--- a/src/wp-admin/js/post.js
+++ b/src/wp-admin/js/post.js
@@ -73,7 +73,7 @@ WPSetThumbnailHTML = function(html){
 
 WPSetThumbnailID = function(id){
 	var field = $('input[value="_thumbnail_id"]', '#list-table');
-	if ( field.size() > 0 ) {
+	if ( field.length > 0 ) {
 		$('#meta\\[' + field.attr('id').match(/[0-9]+/) + '\\]\\[value\\]').text(id);
 	}
 };
diff --git a/src/wp-includes/js/wp-ajax-response.js b/src/wp-includes/js/wp-ajax-response.js
index 31fc897e6f..d35632102b 100644
--- a/src/wp-includes/js/wp-ajax-response.js
+++ b/src/wp-includes/js/wp-ajax-response.js
@@ -24,7 +24,7 @@ var wpAjax = jQuery.extend( {
 				response.supplemental = {};
 				if ( !jQuery( 'supplemental', child ).children().each( function() {
 					response.supplemental[this.nodeName] = jQuery(this).text();
-				} ).size() ) { response.supplemental = false; }
+				} ).length ) { response.supplemental = false; }
 				response.errors = [];
 				if ( !jQuery('wp_error', child).each( function() {
 					var code = jQuery(this).attr('code'), anError, errorData, formField;
@@ -37,7 +37,7 @@ var wpAjax = jQuery.extend( {
 					err += '<p>' + anError.message + '</p>';
 					response.errors.push( anError );
 					parsed.errors = true;
-				} ).size() ) { response.errors = false; }
+				} ).length ) { response.errors = false; }
 				parsed.responses.push( response );
 			} );
 			if ( err.length ) { re.html( '<div class="error">' + err + '</div>' ); }
@@ -54,7 +54,7 @@ var wpAjax = jQuery.extend( {
 	},
 	validateForm: function( selector ) {
 		selector = jQuery( selector );
-		return !wpAjax.invalidateForm( selector.find('.form-required').filter( function() { return jQuery('input:visible', this).val() === ''; } ) ).size();
+		return !wpAjax.invalidateForm( selector.find('.form-required').filter( function() { return jQuery('input:visible', this).val() === ''; } ) ).length;
 	}
 }, wpAjax || { noPerm: 'You do not have permission to do that.', broken: 'An unidentified error has occurred.' } );
 
diff --git a/src/wp-includes/js/wp-lists.js b/src/wp-includes/js/wp-lists.js
index bf34b8c4b9..117e892f72 100644
--- a/src/wp-includes/js/wp-lists.js
+++ b/src/wp-includes/js/wp-lists.js
@@ -336,16 +336,16 @@ wpList = {
 
 		s = $.extend(_s, this.wpList.settings, s);
 
-		if ( !e.size() || !s.what )
+		if ( !e.length || !s.what )
 			return false;
 
 		if ( s.oldId )
 			old = $('#' + s.what + '-' + s.oldId);
 
-		if ( s.id && ( s.id != s.oldId || !old || !old.size() ) )
+		if ( s.id && ( s.id != s.oldId || !old || !old.length ) )
 			$('#' + s.what + '-' + s.id).remove();
 
-		if ( old && old.size() ) {
+		if ( old && old.length ) {
 			old.before(e);
 			old.remove();
 		} else if ( isNaN(s.pos) ) {
@@ -358,7 +358,7 @@ wpList = {
 
 			ref = list.find( '#' + s.pos );
 
-			if ( 1 === ref.size() )
+			if ( 1 === ref.length )
 				ref[ba](e);
 			else
 				list.append(e);
@@ -389,11 +389,11 @@ wpList = {
 
 		e = $(e);
 
-		if ( list.wpList && e.parents( '#' + list.id ).size() )
+		if ( list.wpList && e.parents( '#' + list.id ).length )
 			return;
 
 		e.find(':input').each( function() {
-			if ( $(this).parents('.form-no-clear').size() )
+			if ( $(this).parents('.form-no-clear').length )
 				return;
 
 			t = this.type.toLowerCase();
@@ -437,7 +437,7 @@ wpList = {
 
 		items = $('.list-item:visible', list);
 
-		if ( !items.size() )
+		if ( !items.length )
 			items = $(list).children(':visible');
 
 		eo = [':even',':odd'];