Wife of Siva (4)
I believe the answer is:
kali
'wife of siva' is the definition.
(I know that Kali is married to Shiva)
This is all the clue.
(Other definitions for kali that I've seen before include "Hindu goddess of death" , "Hindu goddess of destruction" , "Terrifying Hindu goddess" , "Indian goddess" , "Hindu consort of Siva" .)