Parade of cars (9)
I believe the answer is:
motorcade
'parade of cars' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for motorcade that I've seen before include "Vehicle procession" , "vehicles in procession" , "Car to demo (anag)" , "Maybe Kennedy's entourage" , "Line of cars escorting a dignitary" .)