Arab's second car (5)
I believe the answer is:
saudi
'arab's' is the definition.
(Saudi is an example)
'second car' is the wordplay.
'second' becomes 's' (common abbreviation).
'car' becomes 'audi' (audi is a german car brand).
's'+'audi'='SAUDI'
(Other definitions for saudi that I've seen before include "Native of Riyadh, perhaps" , "one accustomed to hot, dry conditions?" , "Arab" , "M East citizen" , "One from Riyadh" .)