Norse god with a hammer (4)
I believe the answer is:
thor
'norse god with a hammer' 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 "The Thunderer" , "Comic superhero" , "Norse god of thunder - a weekday is named after him" , "Scandinavian thunder-god" , "One of the Norse gods" .)