Branch gets in male attire (7)
I believe the answer is:
garment
'attire' is the definition.
(I know that Garment is a attire)
'branch gets in male' is the wordplay.
'branch' becomes 'arm' (synonyms).
'gets in' is an insertion indicator.
'male' becomes 'gent' (gent is a kind of male).
'arm' placed within 'gent' is 'GARMENT'.
(Other definitions for garment that I've seen before include "Raiment" , "Covering" , "An article of clothing (7)" , "dress, perhaps" , "Maybe a jacket" .)