Definition of overdrawing:
(v) :
To withdraw more money from an account than there is credit; to make an overdraft
(v) :
(computer graphics) To draw over the top of existing content.
(n) :
(computer graphics) The process by which, during the rendering of a three-dimensional scene, a pixel is replaced by one that is closer to the viewpoint, as determined by their Z coordinates.
(v) :
(archery) To use a device for shooting arrows shorter than the draw of the bow.
(v) :
(music) To draw the air in through a harmonica while adjusting the mouth so that the note goes up a half tone.
(v) :
(dated) To exaggerate.