Polish or north European language being heard (6)
I believe the answer is:
finish
'polish' is the definition.
(as in polishing or finishing a surface)
'north european language being heard' is the wordplay.
'north european language' becomes 'Finnish' (language of Finland).
'being heard' shows a homophone (sound like).
'finnish' sounds like 'FINISH'.
'or' acts as a link.
(Other definitions for finish that I've seen before include "train socially" , "Conclude, end" , "Conclude, wind up" , "Polish, perhaps" , "Bring to an close" .)