Vehicle that’s about right (3)
I believe the answer is:
car
'vehicle' is the definition.
(I've seen this before)
'about right' is the wordplay.
'about' becomes 'ca' (abbreviation for 'circa').
'right' becomes 'r' (common abbreviation).
'ca'+'r'='CAR'
'that's' is the link.
(Other definitions for car that I've seen before include "Wheels" , "Four-wheeled vehicle" , "Hatchback, say?" , "Means of transport" , "Road vehicle; rail coach" .)