Fire alarm (5)
I believe the answer is:
siren
'fire alarm' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for siren that I've seen before include "Alarm - fascinating woman" , "Temptress - makes a loud noise!" , "Bewitching singer,part- woman, part-bird" , "Charmer" , "Rinse (anag) - sea nymph" .)