Shape of the punster's departed parrot? (7)
I believe the answer is:
polygon
'shape' is the definition.
(polygon is a kind of shape)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for polygon that I've seen before include "Straight-sided figure" , "Closed plane figure with three or more straight sides" , "Figure with many sides" , "Closed plane figure bounded by straight sides" , "Plane figure with a number of straight sides" .)