Promgoer's ride (4)
I believe the answer is:
limo
'promgoer's ride' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for limo that I've seen before include "Set of rooms" , "Luxury car" , "Stretched car, often used for partying" , "Long motor" , "Large luxurious car" .)