\Si"ren\, n. [L., fr. Gr. ???: cf. F. sir[`e]ne.]
1. (Class. Myth.) One of three sea nymphs, -- or, according
   to some writers, of two, -- said to frequent an island
   near the coast of Italy, and to sing with such sweetness
   that they lured mariners to destruction.
         Next where the sirens dwell you plow the seas; Their
         song is death, and makes destruction please. --Pope.
2. An enticing, dangerous woman. --Shak.
3. Something which is insidious or deceptive.
         Consumption is a siren.               --W. Irving.
4. A mermaid. [Obs.] --Shak.
5. (Zo["o]l.) Any long, slender amphibian of the genus
   {Siren} or family {Sirenid[ae]}, 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.
6. [F. sir[`e]ne, properly, a siren in sense 1.] (Acoustics)
   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. [Written
   also {sirene}, and {syren}.]

\Si"ren\, a.
Of or pertaining to a siren; bewitching, like a siren;
fascinating; alluring; as, a siren song.