Fraud misleading dupes (5)
I believe the answer is:
pseud
'fraud' is the definition.
('pseud' can be a synonym of 'fraud')
'misleading dupes' is the wordplay.
'misleading' indicates an anagram (I've seen this in other clues).
'dupes' is an anagram of 'PSEUD'.
(Other definitions for pseud that I've seen before include "Poseur (colloq.)" , "Pretentious fraud" , "Fraud -- dupes (anag)" , "Poser" , "Pretentious sort" .)