Heavenly couple, for example, reversing car (6)
I believe the answer is:
gemini
'heavenly couple' is the definition.
(constellation representing twins Castor and Pollux)
'example reversing car' is the wordplay.
'example' becomes 'eg' (short for 'exempli gratia', 'for example' in Latin).
'reversing' says the letters should be written backwards.
'car' becomes 'mini' (Mini Cooper).
'eg' reversed gives 'ge'.
'ge'+'mini'='GEMINI'
'for' is the link.
(Other definitions for gemini that I've seen before include "star group" , "lot of stars" , "May person" , "Zodiacal twins" , "Heavenly sign of the Twins" .)