Offensive husband seen with drink in retreat (4)
I believe the answer is:
push
'offensive' is the definition.
(I've seen this before)
'husband seen with drink in retreat' is the wordplay.
'husband' becomes 'h' (abbreviation).
'seen with' says to put letters next to each other.
'drink' becomes 'sup' (to sup is to drink).
'in retreat' says the letters should be written backwards.
'h'+'sup'='hsup'
'hsup' reversed gives 'PUSH'.
(Other definitions for push that I've seen before include "Promote (commodity)" , "What often proverbially comes to "shove"?" , "Move by exerting force" , "Drive forward" , "Opposite of pull" .)