Slags off advanced coaches (6)
I believe the answer is:
abuses
'slags' is the definition.
Although both the answer and definition are plural nouns, I don't understand how one could define the other.
'advanced coaches' is the wordplay.
'advanced' becomes 'a' (abbreviation).
'coaches' becomes 'buses' ('bus' can be a synonym of 'coach').
'a'+'buses'='ABUSES'
'off' acts as a link.
Can you help me to learn more?
(Other definitions for abuses that I've seen before include "Reviles and insults" , "Treats cruelly" , "Employs or deals with incorrectly" , "Reviles or takes undue advantage." , "Maltreats people or things" .)