Wife leans over in car (6)
I believe the answer is:
wheels
'car' is the definition.
(wheels can informally mean a car)
'wife leans over' is the wordplay.
'wife' becomes 'w'.
'leans over' becomes 'heels' (to heel is to lean or tilt over).
'w'+'heels'='WHEELS'
'in' is the link.
(Other definitions for wheels that I've seen before include "turns round" , "Circular spoked frames" , "Circular frames with spokes" , "Spins on an axis" , "Vehicle" .)