Exposed well-dressed fool (8)
I believe the answer is:
outsmart
'fool' is the definition.
(thesaurus)
'exposed well-dressed' is the wordplay.
'exposed' becomes 'out' (I've seen this in other clues).
'well dressed' becomes 'smart' (I've seen this before).
'out'+'smart'='OUTSMART'
(Other definitions for outsmart that I've seen before include "Fox; deceive" , "Win by clever thinking" , "Defeat by skillful maneuvering" , "Best" , "Excel in cleverness" .)