diff --git a/Doc/library/turtle.rst b/Doc/library/turtle.rst
index 595a244342c..175010b8990 100644
--- a/Doc/library/turtle.rst
+++ b/Doc/library/turtle.rst
@@ -1309,7 +1309,7 @@ Using events
 
    :param fun: a function with two arguments which will be called with the
                coordinates of the clicked point on the canvas
-   :param num: number of the mouse-button, defaults to 1 (left mouse button)
+   :param btn: number of the mouse-button, defaults to 1 (left mouse button)
    :param add: ``True`` or ``False`` -- if ``True``, a new binding will be
                added, otherwise it will replace a former binding
 
@@ -1330,7 +1330,7 @@ Using events
 
    :param fun: a function with two arguments which will be called with the
                coordinates of the clicked point on the canvas
-   :param num: number of the mouse-button, defaults to 1 (left mouse button)
+   :param btn: number of the mouse-button, defaults to 1 (left mouse button)
    :param add: ``True`` or ``False`` -- if ``True``, a new binding will be
                added, otherwise it will replace a former binding
 
@@ -1354,7 +1354,7 @@ Using events
 
    :param fun: a function with two arguments which will be called with the
                coordinates of the clicked point on the canvas
-   :param num: number of the mouse-button, defaults to 1 (left mouse button)
+   :param btn: number of the mouse-button, defaults to 1 (left mouse button)
    :param add: ``True`` or ``False`` -- if ``True``, a new binding will be
                added, otherwise it will replace a former binding
 
@@ -1735,7 +1735,7 @@ Using screen events
 
    :param fun: a function with two arguments which will be called with the
                coordinates of the clicked point on the canvas
-   :param num: number of the mouse-button, defaults to 1 (left mouse button)
+   :param btn: number of the mouse-button, defaults to 1 (left mouse button)
    :param add: ``True`` or ``False`` -- if ``True``, a new binding will be
                added, otherwise it will replace a former binding
 
diff --git a/Lib/turtle.py b/Lib/turtle.py
index 9db564b7eb8..47a94f2a470 100644
--- a/Lib/turtle.py
+++ b/Lib/turtle.py
@@ -1352,7 +1352,7 @@ class TurtleScreen(TurtleScreenBase):
         Arguments:
         fun -- a function with two arguments, the coordinates of the
                clicked point on the canvas.
-        num -- the number of the mouse-button, defaults to 1
+        btn -- the number of the mouse-button, defaults to 1
 
         Example (for a TurtleScreen instance named screen)
 
@@ -3526,7 +3526,7 @@ class RawTurtle(TPen, TNavigator):
         Arguments:
         fun --  a function with two arguments, to which will be assigned
                 the coordinates of the clicked point on the canvas.
-        num --  number of the mouse-button defaults to 1 (left mouse button).
+        btn --  number of the mouse-button defaults to 1 (left mouse button).
         add --  True or False. If True, new binding will be added, otherwise
                 it will replace a former binding.
 
@@ -3547,7 +3547,7 @@ class RawTurtle(TPen, TNavigator):
         Arguments:
         fun -- a function with two arguments, to which will be assigned
                 the coordinates of the clicked point on the canvas.
-        num --  number of the mouse-button defaults to 1 (left mouse button).
+        btn --  number of the mouse-button defaults to 1 (left mouse button).
 
         Example (for a MyTurtle instance named joe):
         >>> class MyTurtle(Turtle):
@@ -3572,7 +3572,7 @@ class RawTurtle(TPen, TNavigator):
         Arguments:
         fun -- a function with two arguments, to which will be assigned
                the coordinates of the clicked point on the canvas.
-        num -- number of the mouse-button defaults to 1 (left mouse button).
+        btn -- number of the mouse-button defaults to 1 (left mouse button).
 
         Every sequence of mouse-move-events on a turtle is preceded by a
         mouse-click event on that turtle.