Vehicle not returning the container (6)
I believe the answer is:
carton
'the container' is the definition.
(carton is a kind of container)
'vehicle not returning' is the wordplay.
'vehicle' becomes 'car' (car is a kind of vehicle).
'returning' shows that the letters should be reversed in order.
'not' backwards is 'ton'.
'car'+'ton'='CARTON'
(Other definitions for carton that I've seen before include "He did a far, far better thing" , "Container for food or liquid" , "Small, light box or container" , "Sydney -, Tale of Two Cities hero" , "Light cardboard box" .)