Hammer wielder of myth (4)
I believe the answer is:
thor
'hammer wielder of myth' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for thor that I've seen before include "Thursday is named after this Scandinavian god" , "Son of Odin and Freya" , "Norse god for whom Thursday is named" , "Mythical figure" , "The Thunderer" .)