Guy undressed outside shower (7)
I believe the answer is:
barrage
'shower' is the definition.
(thesaurus)
'guy undressed outside' is the wordplay.
'guy' becomes 'rag' (both can mean to tease or mock).
'undressed' becomes 'bare' (I've seen this in another clue).
'outside' indicates putting letters inside.
'rag' inserted into 'bare' is 'BARRAGE'.
(Other definitions for barrage that I've seen before include "Continuous fusillade or a torrent of questions" , "Artillery bombardment; flood barrier" , "Continuous artillery fire" , "number of shots" , "Heavy, continuous fire" .)