Performer's attire's fantastic (7)
I believe the answer is:
artiste
'performer's' is the definition.
(artiste is a kind of performer)
'attire's fantastic' is the wordplay.
'fantastic' indicates an anagram.
'attires' with letters rearranged gives 'ARTISTE'.
(Other definitions for artiste that I've seen before include "Tears it (anag.)" , "'Public performer, dancer or singer (7)'" , "Professional performer" , "nightclub entertainer?" , "A sitter for creative person" .)