Smart nudist in gauze clothing (5)
I believe the answer is:
sting
'smart' is the definition.
(both can mean to burn or hurt)
'nudist in gauze clothing' is the wordplay.
'clothing' indicates the answer is hidden within the clue (the solution is covered or clothed by the clue).
'STING' can be found hidden inside 'nudist in gauze'.
(Other definitions for sting that I've seen before include "Goad" , "The pain caused by bee or nettle" , "bit of deception" , "fleece?" , "viz. Gordon Sumner" .)