mouse-avoidance-banish-position

mouse-avoidance-banish-position is a variable defined in `avoid.el'.
Its value is

((frame-or-window . frame)
 (side . right)
 (side-pos . 3)
 (top-or-bottom . top)
 (top-or-bottom-pos . 0))

Documentation:
Position to which Mouse Avoidance mode `banish' moves the mouse.
An alist where keywords mean:
FRAME-OR-WINDOW: banish the mouse to corner of frame or window.
SIDE: banish the mouse on right or left corner of frame or window.
SIDE-POS: Distance from right or left edge of frame or window.
TOP-OR-BOTTOM: banish the mouse to top or bottom of frame or window.
TOP-OR-BOTTOM-POS: Distance from top or bottom edge of frame or window.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 24.3 of Emacs.