Queen of Olympus (4)
I believe the answer is:
hera
'queen of olympus' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for hera that I've seen before include "Divine consort" , "Greek queen of Olympian gods" , "Jealous sister and wife of Zeus" , "Zeus's wife and sister" , "Divinity" .)