An enticing, dangerous woman.

Something which is insidious or deceptive.

A mermaid.

Any long, slender amphibian of the genus Siren or family
Sirenidae, destitute of hind legs and pelvis, and having permanent
external gills as well as lungs. They inhabit the swamps, lagoons, and
ditches of the Southern United States. The more common species (Siren
lacertina) is dull lead-gray in color, and becames two feet long.

An instrument for producing musical tones and for
ascertaining the number of sound waves or vibrations per second which
produce a note of a given pitch. The sounds are produced by a
perforated rotating disk or disks. A form with two disks operated by
steam or highly compressed air is used sounding an alarm to vessels in
fog.

Of or pertaining to a siren; bewitching, like a siren;
fascinating; alluring; as, a siren song.