Chief Norse god (4)
I believe the answer is:
odin
'chief norse god' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for odin that I've seen before include "who's worshipped" , "mythological personage" , "Supreme Scandinavian god - what a racket" , "Legendary Scandinavian" , "In Scandinavian myth the supreme god and creator" .)