Country singer seen by king (5)
I believe the answer is:
kenya
'country' is the definition.
(I know that Kenya is a country)
'singer seen by king' is the wordplay.
'singer' becomes 'enya' (I can't explain this - if you can you should give a lot more credence to this answer).
'seen by' means one lot of letters go next to another.
'king' becomes 'K' (abbreviation for king in chess).
'enya' put after 'k' is 'KENYA'.
Can you help me to learn more?
(Other definitions for kenya that I've seen before include "East African republic" , "Nairobi's country" , "Land" , "Kikuyus' country" , "E African country" .)