Wailing spirit (7)
I believe the answer is:
banshee
'wailing spirit' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for banshee that I've seen before include "Wailing female spirit" , "Ominous wailing spirit" , "She predicts death in Ireland" , "Sign of imminent death" , "Irish female spirit who warns of an impending death" .)