diff --git a/mindplot/src/main/javascript/widget/Menu.js b/mindplot/src/main/javascript/widget/Menu.js
index d0ddffb2..b5f72e2c 100644
--- a/mindplot/src/main/javascript/widget/Menu.js
+++ b/mindplot/src/main/javascript/widget/Menu.js
@@ -271,7 +271,7 @@ mindplot.widget.Menu = new Class({
         this._addButton('addTopic', true, false, function () {
             designer.createChildForSelectedNode();
         });
-        this._registerTooltip('addTopics', $msg('ADD_TOPIC'), "Enter");
+        this._registerTooltip('addTopic', $msg('ADD_TOPIC'), "Enter");
 
 
         this._addButton('deleteTopic', true, true, function () {