Greek god seen in a restaurant (4)
I believe the answer is:
ares
'greek god' is the definition.
(Ares is an example)
'a restaurant' is the wordplay.
'restaurant' becomes 'res' (I can't justify this - if you can you should give a lot more credence to this answer).
'a'+'res'='ARES'
'seen in' acts as a link.
Can you help me to learn more?
(Other definitions for ares that I've seen before include "Greek god of war" , "War-god" , "Belligerent god" , "figure of worship" , "Olympian" .)