Country song mostly welcomed by Atlantic? (6)
I believe the answer is:
poland
'country' is the definition.
(Poland is an example)
'song mostly welcomed by atlantic?' is the wordplay.
'song mostly' becomes 'la' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'welcomed by' means one lot of letters goes inside another (letters welcomed inside).
'atlantic?' becomes 'pond' (as in 'across the pond').
'la' going within 'pond' is 'POLAND'.
Can you help me to learn more?
(Other definitions for poland that I've seen before include "EU member" , "Wroclaw's country" , "Slovakia's northern neighbour" , "in E" , "European nation" .)