Stages of various shapes (6)
I believe the answer is:
phases
'stages' is the definition.
('phase' can be a synonym of 'stage')
'various shapes' is the wordplay.
'various' indicates anagramming the letters.
'shapes' is an anagram of 'PHASES'.
'of' acts as a link.
(Other definitions for phases that I've seen before include "Distinct stages of development" , "Stages in processes" , "Stages in process of change" , "Shapes into stages in process" .)