Car's ability revolving on friends (7,6)
I believe the answer is:
turning circle
'car's ability' is the definition.
The definition suggests a singular noun which matches the answer.
'revolving on friends' is the wordplay.
'revolving' becomes 'turning' (synonyms).
'on friends' becomes 'circle' (I am not sure about this - if you are sure you should believe this answer much more).
'turning'+'circle'='TURNING-CIRCLE'
Can you help me to learn more?
(Other definitions for turning circle that I've seen before include "Tight curve for vehicle" , "Smallest possible arc for a vehicle" , "revolutionary movement" , "Measure of vehicle's manoeuvrability" , "Smallest space for vehicle to go about" .)