diff --git a/Lib/idlelib/macosxSupport.py b/Lib/idlelib/macosxSupport.py
index bf472c22d2d..8f86ca69280 100644
--- a/Lib/idlelib/macosxSupport.py
+++ b/Lib/idlelib/macosxSupport.py
@@ -9,7 +9,7 @@ def runningAsOSXApp():
     """
     Returns True if Python is running from within an app on OSX.
     If so, assume that Python was built with Aqua Tcl/Tk rather than
-    X11 Tck/Tk.
+    X11 Tcl/Tk.
     """
     return (sys.platform == 'darwin' and '.app' in sys.executable)