A mate in the country (5)
I believe the answer is:
china
I believe this is a double definition.
'a mate' is the first definition.
(cockney rhyming slang, mate is china plate)
'country' is the second definition.
(China is an example)
'in the' is the link.
(Other definitions for china that I've seen before include "High quality porcelain" , "The most populous country in the world" , "Ceramic material" , "friend or companion" , "Large country; mate" .)