Form different heaps (5)
I believe the answer is:
shape
'form' is the definition.
(I know that form can be written as shape)
'different heaps' is the wordplay.
'different' is an anagram indicator (letters placed in a different order).
'heaps' is an anagram of 'SHAPE'.
(Other definitions for shape that I've seen before include "Control development of" , "Heaps (anag.)" , "Form, figure" , "Mould into new phase" , "'Figure, outline (5)'" .)