Stupid new fashion, almost (6)
I believe the answer is:
oafish
'stupid' is the definition.
(I've seen this in another clue)
'new fashion almost' is the wordplay.
'new' indicates an anagram.
'almost' means to remove the last letter (most of the word but not all of it).
'fashion' with its last letter taken away is 'fashio'.
'fashio' with letters rearranged gives 'OAFISH'.
(Other definitions for oafish that I've seen before include "lacking elegance?" , "having poor manners" , "Loutish" , "Like a boorish person" , "Like a lout" .)