Wave from posh car (6)
I believe the answer is:
roller
This clue is a double definition.
'wave' is the first definition.
(I know that roller is a type of wave)
'posh car' is the second definition.
(abbreviation for Rolls Royce)
'from' is the link.
(Other definitions for roller that I've seen before include "Sea wave; brilliant bird" , "expensive car" , "Bright bird; cylinder" , "One may be employed to paint" , "Large sea wave and hair-curler" .)