Posers seldom resolved (6)
I believe the answer is:
models
'posers' is the definition.
('model' can be a synonym of 'poser')
'seldom resolved' is the wordplay.
'resolved' indicates an anagram.
'seldom' with letters rearranged gives 'MODELS'.
(Other definitions for models that I've seen before include "Clothes exhibitionists for the catwalk" , "Mannequins or examplars" , "Exemplars or mannequins" , "Human clothes horses or protoypes" , "Prototypes" .)