Copper with a party in royal country (7)
I believe the answer is:
ecuador
'country' is the definition.
(I know that Ecuador is a country)
'copper with a party in royal' is the wordplay.
I cannot really understand how this works, but
'copper' could be 'cu' (chemical symbol) and 'cu' is found in the answer.
'a' is found in the answer.
'party' could be 'do' (do is a kind of party) and 'do' is found within the answer.
'royal' could be 'er' (abbreviation for Elizabeth Regina) and 'er' is found within the remaining letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for ecuador that I've seen before include "Country of the Galapagos Islands" , "Quito's nation" , "South American republic" , "S. American nation" , "SA country" .)