diff --git a/src/wp-admin/includes/class-wp-posts-list-table.php b/src/wp-admin/includes/class-wp-posts-list-table.php
index 506dded3fd..983a274f85 100644
--- a/src/wp-admin/includes/class-wp-posts-list-table.php
+++ b/src/wp-admin/includes/class-wp-posts-list-table.php
@@ -1550,10 +1550,13 @@ class WP_Posts_List_Table extends WP_List_Table {
 	<?php if ( count( $flat_taxonomies ) && !$bulk ) : ?>
 
 	<?php foreach ( $flat_taxonomies as $taxonomy ) : ?>
-		<?php if ( current_user_can( $taxonomy->cap->assign_terms ) ) : ?>
+		<?php if ( current_user_can( $taxonomy->cap->assign_terms ) ) :
+			$taxonomy_name = esc_attr( $taxonomy->name );
+	
+			?>
 			<label class="inline-edit-tags">
 				<span class="title"><?php echo esc_html( $taxonomy->labels->name ) ?></span>
-				<textarea cols="22" rows="1" name="tax_input[<?php echo esc_attr( $taxonomy->name )?>]" class="tax_input_<?php echo esc_attr( $taxonomy->name )?>"></textarea>
+				<textarea data-wp-taxonomy="<?php echo $taxonomy_name; ?>" cols="22" rows="1" name="tax_input[<?php echo $taxonomy_name; ?>]" class="tax_input_<?php echo $taxonomy_name; ?>"></textarea>
 			</label>
 		<?php endif; ?>
 
diff --git a/src/wp-admin/includes/meta-boxes.php b/src/wp-admin/includes/meta-boxes.php
index b345e6f7ec..98e20de417 100644
--- a/src/wp-admin/includes/meta-boxes.php
+++ b/src/wp-admin/includes/meta-boxes.php
@@ -431,7 +431,7 @@ function post_tags_meta_box( $post, $box ) {
  	<?php if ( $user_can_assign_terms ) : ?>
 	<div class="ajaxtag hide-if-no-js">
 		<label class="screen-reader-text" for="new-tag-<?php echo $tax_name; ?>"><?php echo $taxonomy->labels->add_new_item; ?></label>
-		<p><input type="text" id="new-tag-<?php echo $tax_name; ?>" name="newtag[<?php echo $tax_name; ?>]" class="newtag form-input-tip" size="16" autocomplete="off" aria-describedby="new-tag-<?php echo $tax_name; ?>-desc" value="" />
+		<p><input data-wp-taxonomy="<?php echo $tax_name; ?>" type="text" id="new-tag-<?php echo $tax_name; ?>" name="newtag[<?php echo $tax_name; ?>]" class="newtag form-input-tip" size="16" autocomplete="off" aria-describedby="new-tag-<?php echo $tax_name; ?>-desc" value="" />
 		<input type="button" class="button tagadd" value="<?php esc_attr_e('Add'); ?>" /></p>
 	</div>
 	<p class="howto" id="new-tag-<?php echo $tax_name; ?>-desc"><?php echo $taxonomy->labels->separate_items_with_commas; ?></p>
diff --git a/src/wp-admin/js/inline-edit-post.js b/src/wp-admin/js/inline-edit-post.js
index 3a65805e3e..9582707479 100644
--- a/src/wp-admin/js/inline-edit-post.js
+++ b/src/wp-admin/js/inline-edit-post.js
@@ -83,7 +83,7 @@ inlineEditPost = {
 	},
 
 	setBulk : function(){
-		var te = '', type = this.type, tax, c = true;
+		var te = '', type = this.type, c = true;
 		this.revert();
 
 		$( '#bulk-edit td' ).attr( 'colspan', $( 'th:visible, td:visible', '.widefat:first thead' ).length );
@@ -114,9 +114,9 @@ inlineEditPost = {
 
 		// enable autocomplete for tags
 		if ( 'post' === type ) {
-			// support multi taxonomies?
-			tax = 'post_tag';
-			$('tr.inline-editor textarea[name="tax_input['+tax+']"]').suggest( ajaxurl + '?action=ajax-tag-search&tax=' + tax, { delay: 500, minchars: 2, multiple: true, multipleSep: inlineEditL10n.comma } );
+			$( 'tr.inline-editor textarea[data-wp-taxonomy]' ).each( function ( i, element ) {
+				$( element ).wpTagsSuggest();
+			} );
 		}
 		$('html, body').animate( { scrollTop: 0 }, 'fast' );
 	},
@@ -196,7 +196,7 @@ inlineEditPost = {
 				textarea.val(terms);
 			}
 
-			textarea.suggest( ajaxurl + '?action=ajax-tag-search&tax=' + taxname, { delay: 500, minchars: 2, multiple: true, multipleSep: inlineEditL10n.comma } );
+			textarea.wpTagsSuggest();
 		});
 
 		// handle the post status
diff --git a/src/wp-admin/js/tags-box.js b/src/wp-admin/js/tags-box.js
index af823ac4e6..d4cad9fb24 100644
--- a/src/wp-admin/js/tags-box.js
+++ b/src/wp-admin/js/tags-box.js
@@ -4,6 +4,8 @@
 var tagBox, array_unique_noempty;
 
 ( function( $ ) {
+	var tagDelimiter = ( window.tagsSuggestL10n && window.tagsSuggestL10n.tagDelimiter ) || ',';
+
 	// Return an array with any duplicate, whitespace or empty values removed
 	array_unique_noempty = function( array ) {
 		var out = [];
@@ -20,13 +22,17 @@ var tagBox, array_unique_noempty;
 	};
 
 	tagBox = {
-		clean : function(tags) {
-			var comma = window.tagsBoxL10n.tagDelimiter;
-			if ( ',' !== comma )
-				tags = tags.replace(new RegExp(comma, 'g'), ',');
+		clean : function( tags ) {
+			if ( ',' !== tagDelimiter ) {
+				tags = tags.replace( new RegExp( tagDelimiter, 'g' ), ',' );
+			}
+
 			tags = tags.replace(/\s*,\s*/g, ',').replace(/,+/g, ',').replace(/[,\s]+$/, '').replace(/^[,\s]+/, '');
-			if ( ',' !== comma )
-				tags = tags.replace(/,/g, comma);
+
+			if ( ',' !== tagDelimiter ) {
+				tags = tags.replace( /,/g, tagDelimiter );
+			}
+
 			return tags;
 		},
 
@@ -35,8 +41,7 @@ var tagBox, array_unique_noempty;
 				num = id.split('-check-num-')[1],
 				taxbox = $(el).closest('.tagsdiv'),
 				thetags = taxbox.find('.the-tags'),
-				comma = window.tagsBoxL10n.tagDelimiter,
-				current_tags = thetags.val().split( comma ),
+				current_tags = thetags.val().split( tagDelimiter ),
 				new_tags = [];
 
 			delete current_tags[num];
@@ -48,7 +53,7 @@ var tagBox, array_unique_noempty;
 				}
 			});
 
-			thetags.val( this.clean( new_tags.join( comma ) ) );
+			thetags.val( this.clean( new_tags.join( tagDelimiter ) ) );
 
 			this.quickClicks( taxbox );
 			return false;
@@ -65,7 +70,7 @@ var tagBox, array_unique_noempty;
 
 			disabled = thetags.prop('disabled');
 
-			current_tags = thetags.val().split( window.tagsBoxL10n.tagDelimiter );
+			current_tags = thetags.val().split( tagDelimiter );
 			tagchecklist.empty();
 
 			$.each( current_tags, function( key, val ) {
@@ -106,8 +111,7 @@ var tagBox, array_unique_noempty;
 		flushTags : function( el, a, f ) {
 			var tagsval, newtags, text,
 				tags = $( '.the-tags', el ),
-				newtag = $( 'input.newtag', el ),
-				comma = window.tagsBoxL10n.tagDelimiter;
+				newtag = $( 'input.newtag', el );
 
 			a = a || false;
 
@@ -118,10 +122,10 @@ var tagBox, array_unique_noempty;
 			}
 
 			tagsval = tags.val();
-			newtags = tagsval ? tagsval + comma + text : text;
+			newtags = tagsval ? tagsval + tagDelimiter + text : text;
 
 			newtags = this.clean( newtags );
-			newtags = array_unique_noempty( newtags.split( comma ) ).join( comma );
+			newtags = array_unique_noempty( newtags.split( tagDelimiter ) ).join( tagDelimiter );
 			tags.val( newtags );
 			this.quickClicks( el );
 
@@ -153,32 +157,29 @@ var tagBox, array_unique_noempty;
 		},
 
 		init : function() {
-			var t = this, ajaxtag = $('div.ajaxtag');
+			var ajaxtag = $('div.ajaxtag');
 
 			$('.tagsdiv').each( function() {
-				tagBox.quickClicks(this);
+				tagBox.quickClicks( this );
 			});
 
-			$('.tagadd', ajaxtag).click(function(){
-				t.flushTags( $(this).closest('.tagsdiv') );
+			$( '.tagadd', ajaxtag ).click( function() {
+				tagBox.flushTags( $( this ).closest( '.tagsdiv' ) );
 			});
 
-			$('input.newtag', ajaxtag).keyup(function(e){
-				if ( 13 == e.which ) {
-					tagBox.flushTags( $(this).closest('.tagsdiv') );
-					return false;
+			$( 'input.newtag', ajaxtag ).keyup( function( event ) {
+				if ( 13 == event.which ) {
+					tagBox.flushTags( $( this ).closest( '.tagsdiv' ) );
+					event.preventDefault();
+					event.stopPropagation();
 				}
-			}).keypress(function(e){
-				if ( 13 == e.which ) {
-					e.preventDefault();
-					return false;
+			}).keypress( function( event ) {
+				if ( 13 == event.which ) {
+					event.preventDefault();
+					event.stopPropagation();
 				}
-			}).each( function() {
-				var tax = $(this).closest('div.tagsdiv').attr('id');
-				$(this).suggest(
-					ajaxurl + '?action=ajax-tag-search&tax=' + tax,
-					{ delay: 500, minchars: 2, multiple: true, multipleSep: window.tagsBoxL10n.tagDelimiter }
-				);
+			}).each( function( i, element ) {
+				$( element ).wpTagsSuggest();
 			});
 
 			// save tags on post save/publish
diff --git a/src/wp-admin/js/tags-suggest.js b/src/wp-admin/js/tags-suggest.js
new file mode 100644
index 0000000000..b9e1632120
--- /dev/null
+++ b/src/wp-admin/js/tags-suggest.js
@@ -0,0 +1,167 @@
+( function( $ ) {
+	var tempID = 0;
+	var separator = ( window.tagsSuggestL10n && window.tagsSuggestL10n.tagDelimiter ) || ',';
+
+	function split( val ) {
+		return val.split( new RegExp( separator + '\\s*' ) );
+	}
+
+	function getLast( term ) {
+		return split( term ).pop();
+	}
+
+	$.fn.wpTagsSuggest = function( options ) {
+		var cache;
+		var last;
+		var $element = $( this );
+
+		options = options || {};
+		
+		var taxonomy = options.taxonomy || $element.attr( 'data-wp-taxonomy' ) || 'post_tag';
+		
+		delete( options.taxonomy );
+
+		options = $.extend( {
+			source: function( request, response ) {				
+				var term;
+
+				if ( last === request.term ) {
+					response( cache );
+					return;
+				}
+
+				term = getLast( request.term );
+
+				$.get( window.ajaxurl, {
+					action: 'ajax-tag-search',
+					tax: taxonomy,
+					q: term
+				} ).always( function() {
+					$element.removeClass( 'ui-autocomplete-loading' ); // UI fails to remove this sometimes?
+				} ).done( function( data ) {
+					var value;
+					var terms = [];
+
+					if ( data ) {
+						data = data.split( '\n' );
+
+						for ( value in data ) {
+							var id = ++tempID;
+
+							terms.push({
+								id: id,
+								name: data[value]
+							});
+						}
+
+						cache = terms;
+						response( terms );
+					} else {
+						response( terms );
+					}
+				} );
+
+				last = request.term;
+			},
+			focus: function( event, ui ) {
+				$element.attr( 'aria-activedescendant', 'wp-tags-autocomplete-' + ui.item.id );
+
+				// Don't empty the input field when using the arrow keys to
+				// highlight items. See api.jqueryui.com/autocomplete/#event-focus
+				event.preventDefault();
+			},
+			select: function( event, ui ) {
+				var tags = split( $element.val() );
+				// Remove the last user input.
+				tags.pop();
+				// Append the new tag and an empty element to get one more separator at the end.
+				tags.push( ui.item.name, '' );
+
+				$element.val( tags.join( separator + ' ' ) );
+
+				if ( $.ui.keyCode.TAB === event.keyCode ) {
+					if ( typeof window.uiAutocompleteL10n !== 'undefined' ) {
+						// Audible confirmation message when a tag has been selected.
+						window.wp.a11y.speak( window.uiAutocompleteL10n.itemSelected );
+					}
+
+					event.preventDefault();
+				} else if ( $.ui.keyCode.ENTER === event.keyCode ) {
+					// Do not close Quick Edit / Bulk Edit
+					event.preventDefault();
+					event.stopPropagation();
+				}
+
+				return false;
+			},
+			open: function() {
+				$element.attr( 'aria-expanded', 'true' );
+			},
+			close: function() {
+				$element.attr( 'aria-expanded', 'false' );
+			},
+			minLength: 2,
+			position: {
+				my: 'left top+2'
+			},
+			messages: {
+				noResults: ( typeof window.uiAutocompleteL10n !== 'undefined' ) ? window.uiAutocompleteL10n.noResults : '',
+				results: function( number ) {
+					if ( typeof window.uiAutocompleteL10n !== 'undefined' ) {
+						if ( number > 1 ) {
+							return window.uiAutocompleteL10n.manyResults.replace( '%d', number );
+						}
+
+						return window.uiAutocompleteL10n.oneResult;
+					}
+				}
+			}
+		}, options );
+
+		$element.on( 'keydown', function() {
+			$element.removeAttr( 'aria-activedescendant' );
+		} )
+		.autocomplete( options )
+		.autocomplete( 'instance' )._renderItem = function( ul, item ) {
+			return $( '<li role="option" id="wp-tags-autocomplete-' + item.id + '">' )
+				.text( item.name )
+				.appendTo( ul );
+		};
+
+		$element.attr( {
+			'role': 'combobox',
+			'aria-autocomplete': 'list',
+			'aria-expanded': 'false',
+			'aria-owns': $element.autocomplete( 'widget' ).attr( 'id' )
+		} )
+		.on( 'focus', function() {
+			var inputValue = split( $element.val() ).pop();
+
+			// Don't trigger a search if the field is empty.
+			// Also, avoids screen readers announce `No search results`.
+			if ( inputValue ) {
+				$element.autocomplete( 'search' );
+			}
+		} )
+		// Returns a jQuery object containing the menu element.
+		.autocomplete( 'widget' )
+			.addClass( 'wp-tags-autocomplete' )
+			.attr( 'role', 'listbox' )
+			.removeAttr( 'tabindex' ) // Remove the `tabindex=0` attribute added by jQuery UI.
+
+			// Looks like Safari and VoiceOver need an `aria-selected` attribute. See ticket #33301.
+			// The `menufocus` and `menublur` events are the same events used to add and remove
+			// the `ui-state-focus` CSS class on the menu items. See jQuery UI Menu Widget.
+			.on( 'menufocus', function( event, ui ) {
+				ui.item.attr( 'aria-selected', 'true' );
+			})
+			.on( 'menublur', function() {
+				// The `menublur` event returns an object where the item is `null`
+				// so we need to find the active item with other means.
+				$( this ).find( '[aria-selected="true"]' ).removeAttr( 'aria-selected' );
+			});
+			
+		return this;
+	};
+
+}( jQuery ) );
diff --git a/src/wp-includes/script-loader.php b/src/wp-includes/script-loader.php
index a7019b039f..e67997a994 100644
--- a/src/wp-includes/script-loader.php
+++ b/src/wp-includes/script-loader.php
@@ -234,6 +234,7 @@ function wp_default_scripts( &$scripts ) {
 		'oneResult' => __( '1 result found. Use up and down arrow keys to navigate.' ),
 		/* translators: %d: Number of results found when using jQuery UI Autocomplete */
 		'manyResults' => __( '%d results found. Use up and down arrow keys to navigate.' ),
+		'itemSelected' => __( 'Item selected.' ),
 	) );
 
 	// deprecated, not used in core, most functionality is included in jQuery 1.3
@@ -241,7 +242,6 @@ function wp_default_scripts( &$scripts ) {
 
 	// jQuery plugins
 	$scripts->add( 'jquery-color', "/wp-includes/js/jquery/jquery.color.min.js", array('jquery'), '2.1.1', 1 );
-	$scripts->add( 'suggest', "/wp-includes/js/jquery/suggest$suffix.js", array('jquery'), '1.1-20110113', 1 );
 	$scripts->add( 'schedule', '/wp-includes/js/jquery/jquery.schedule.js', array('jquery'), '20m', 1 );
 	$scripts->add( 'jquery-query', "/wp-includes/js/jquery/jquery.query.js", array('jquery'), '2.1.7', 1 );
 	$scripts->add( 'jquery-serialize-object', "/wp-includes/js/jquery/jquery.serialize-object.js", array('jquery'), '0.2', 1 );
@@ -249,6 +249,9 @@ function wp_default_scripts( &$scripts ) {
 	$scripts->add( 'jquery-table-hotkeys', "/wp-includes/js/jquery/jquery.table-hotkeys$suffix.js", array('jquery', 'jquery-hotkeys'), false, 1 );
 	$scripts->add( 'jquery-touch-punch', "/wp-includes/js/jquery/jquery.ui.touch-punch.js", array('jquery-ui-widget', 'jquery-ui-mouse'), '0.2.2', 1 );
 
+	// Not used any more, registered for backwards compatibility.
+	$scripts->add( 'suggest', "/wp-includes/js/jquery/suggest$suffix.js", array('jquery'), '1.1-20110113', 1 );
+
 	// Masonry v2 depended on jQuery. v3 does not. The older jquery-masonry handle is a shiv.
 	// It sets jQuery as a dependency, as the theme may have been implicitly loading it this way.
 	$scripts->add( 'imagesloaded', "/wp-includes/js/imagesloaded.min.js", array(), '3.2.0', 1 );
@@ -523,8 +526,10 @@ function wp_default_scripts( &$scripts ) {
 			'postBoxEmptyString' => __( 'Drag boxes here' ),
 		) );
 
-		$scripts->add( 'tags-box', "/wp-admin/js/tags-box$suffix.js", array( 'jquery', 'suggest' ), false, 1 );
-		did_action( 'init' ) && $scripts->localize( 'tags-box', 'tagsBoxL10n', array(
+		$scripts->add( 'tags-box', "/wp-admin/js/tags-box$suffix.js", array( 'jquery', 'tags-suggest' ), false, 1 );
+
+		$scripts->add( 'tags-suggest', "/wp-admin/js/tags-suggest$suffix.js", array( 'jquery-ui-autocomplete', 'wp-a11y' ), false, 1 );
+		did_action( 'init' ) && $scripts->localize( 'tags-suggest', 'tagsSuggestL10n', array(
 			'tagDelimiter' => _x( ',', 'tag delimiter' ),
 		) );
 
@@ -584,7 +589,7 @@ function wp_default_scripts( &$scripts ) {
 
 		$scripts->add( 'theme', "/wp-admin/js/theme$suffix.js", array( 'wp-backbone', 'wp-a11y' ), false, 1 );
 
-		$scripts->add( 'inline-edit-post', "/wp-admin/js/inline-edit-post$suffix.js", array( 'jquery', 'suggest', 'wp-a11y' ), false, 1 );
+		$scripts->add( 'inline-edit-post', "/wp-admin/js/inline-edit-post$suffix.js", array( 'jquery', 'tags-suggest', 'wp-a11y' ), false, 1 );
 		did_action( 'init' ) && $scripts->localize( 'inline-edit-post', 'inlineEditL10n', array(
 			'error'      => __( 'Error while saving the changes.' ),
 			'ntdeltitle' => __( 'Remove From Bulk Edit' ),