Buff wife punches lover (4)
I believe the answer is:
fawn
'buff' is the definition.
The answer and definition can be both human attributes as well as being singular nouns.
Perhaps you can see a link between them that I can't see?
'wife punches lover' is the wordplay.
'wife' becomes 'w' (abbreviation).
'punches' is an insertion indicator (some letters punch a hole in others).
'lover' becomes 'fan' (synonyms).
'w' put into 'fan' is 'FAWN'.
Can you help me to learn more?
(Other definitions for fawn that I've seen before include "Yellowish brown; grovel" , "Greyish brown" , "Light brown colour" , "Try to win favour by being obsequious" , "crawl" .)