Fashions in different phases (6)
I believe the answer is:
shapes
'fashions' is the definition.
(fashion can mean to shape or mould)
'different phases' is the wordplay.
'different' indicates anagramming the letters.
'phases' anagrammed gives 'SHAPES'.
'in' is the link.
(Other definitions for shapes that I've seen before include "Moulds in phases" , "Oblong, square etc" , "Triangle, globe etc" , "Oblong and square, say" , "models" .)