Ban being naughtily bared (5)
I believe the answer is:
debar
'ban' is the definition.
(thesaurus)
'naughtily bared' is the wordplay.
'naughtily' indicates an anagram.
'bared' is an anagram of 'DEBAR'.
'being' is the link.
(Other definitions for debar that I've seen before include "Keep out" , "Large advert" , "Exclude - bread (anag)" , "Refuse to admit" , "Rule out" .)