Posh car that might be stuck in Barnet (6)
I believe the answer is:
roller
'posh car' is the definition.
(abbreviation for Rolls Royce)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for roller that I've seen before include "Big wave or hair setter" , "Heavy sea wave and hair curler" , "Swelling wave; bird" , "A large wave or a hair shaper" , "sort of blind" .)