Tom, say, catches nude show (7)
I believe the answer is:
cabaret
'show' is the definition.
(I know that cabaret is a type of show)
'tom say catches nude' is the wordplay.
'tom say' becomes 'cat' (a tom is a male cat).
'catches' means one lot of letters goes inside another.
'nude' becomes 'bare' (synonyms).
'cat' enclosing 'bare' is 'CABARET'.
(Other definitions for cabaret that I've seen before include "Musical - nightclub entertainment" , "Floor show and name of great musical" , "Entertainment at night club" , "Bear cat (anag.)" , "Entertainment provided in a nightclub" .)