Outsize garment, wet (3,5,6)
I believe the answer is:
big girls blouse
'wet' is the definition.
(both can mean a weak man)
'outsize garment' is the wordplay.
I cannot really see how this works, but
'outsize' could be 'big' (similar in meaning) and 'big' is found within the answer.
'garment' could be 'blouse' (blouse is a kind of garment) and 'blouse' is present in the answer.
The remaining letters 'girls' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
(Other definitions for big girls blouse that I've seen before include "older sister was into?" , "concealing large bra?" , "over-sensitive man" , "wet" , "garment for Bertha?" .)