siren

noun

1.
a woman who is considered to be dangerously seductive
maneater Delilah enchantress femme fatale temptress
2.
a warning signal that is a loud wailing sound
3.
an acoustic device producing a loud often wailing sound as a signal or warning
4.
eellike aquatic North American salamander with small forelimbs and no hind limbs; have permanent external gills