Abandon barring women boarding vehicle? On the contrary, becoming insulting (7)
I believe the answer is:
abusive
'insulting' is the definition.
(synonyms)
'abandon barring women boarding vehicle? on the contrary' is the wordplay.
I cannot quite see how this works, but
'vehicle?' could be 'bus' (bus is a kind of vehicle) and 'bus' is found within the answer.
This may be the basis of clue (or it may be nonsense).
'becoming' acts as a link.
(Other definitions for abusive that I've seen before include "Insulting, foul-mouthed" , "Reviling with coarse language" , "Vituperative" , "Calumniating" , "Given to hurling insults" .)