Major Norse deity (4)
I believe the answer is:
'major norse deity' 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 "I nod to the Norse deity" , "Scandinavian war god" , "Legendary Scandinavian" , "In Scandinavian myth the supreme god and creator" , "Supreme Scandinavian god - what a racket" .)