Ancient northerner chosen to be heard (4)
I believe the answer is:
pict
'ancient northerner' is the definition.
(the Picts were an ancient people of Scotland)
'chosen to be heard' is the wordplay.
'chosen' becomes 'picked' (picking is a kind of choosing).
'to be heard' shows a homophone (sound like).
'picked' is a homophone of 'PICT'.
(Other definitions for pict that I've seen before include "N. British tribesman" , "Northerner" , "Ancient Scot in Roman times" , "Very old person" , "Literary term for painted woman" .)