Carport (6)
I believe the answer is:
garage
'carport' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for garage that I've seen before include "lock-up?" , "Source of 4 dn or 16 dn" , "Car's home (or hospital?)" , "Building for housing automobiles" , "Car repair shop" .)