Copper is at home with Oriental cooking (7)
I believe the answer is:
cuisine
'cooking' is the definition.
('cuisine' can be a synonym of 'cooking')
'copper is at home with oriental' is the wordplay.
'copper' becomes 'cu' (chemical symbol).
'at home' becomes 'in' ('in' can be similar in meaning to 'at home').
'with' means one lot of letters go next to another.
'oriental' becomes 'e'.
'cu'+'is'+'in'+'e'='CUISINE'
(Other definitions for cuisine that I've seen before include "Local cooking style" , "(Regional) style of cooking" , "The food" , "French cooking?" , "It can be French, Italian or Spanish in a restaurant and tasty" .)