Annoy if coming between the sexes (4)
I believe the answer is:
miff
'annoy' is the definition.
(I've seen this before)
'if coming between the sexes' is the wordplay.
'coming between' is an insertion indicator.
'the sexes' becomes 'mf' (I can't justify this - if you can you should believe this answer much more).
'if' placed into 'mf' is 'MIFF'.
Can you help me to learn more?
(Other definitions for miff that I've seen before include "causes resentment" , "Put in a bad mood" , "Annoy - offend" , "Take offence" , "minor quarrel" .)