A woman who tempts men with bewitching sweetness.
Example:
Reporters treated her like a sex symbol, but she lacked the graceful presence and air of mystery of a real siren.
The sirens were a group of partly human female creatures in Greek mythology that lures sailors onto destructive rocks with their singing. Odysseus and his men encountered the sirens after leaving Troy. The only way to sail by them safely was to make oneself deaf to their enchanting song, so Odysseus packed the men's ears with wax. But he himself, ever curious, wanted to hear, so he had himself tied to the mast to keep from flinging himself into the water or steering his ship toward sure destruction. A siren today is almost always a woman, though she need not sing or cause shipwrecks. But a siren song may be any appeal that lures a person to act against his or her better judgment.