One who’s against work with model (7)
I believe the answer is:
opposer
'one who's against' is the definition.
I can't tell whether this definition defines the answer.
'work with model' is the wordplay.
'work' becomes 'op' (abbreviation for opus).
'with' is a charade indicator (letters next to each other).
'model' becomes 'poser' (synonyms).
'op'+'poser'='OPPOSER'
Can you help me to learn more?
(Other definitions for opposer that I've seen before include "Adversary" , "One who takes on" , "One offering resistance" , "The one against the motion" , "Contender" .)