In Greek mythology, Maenads [MEE-nads] were female worshippers of Dionysus, the Greek god of mystery, wine and intoxication. The word literally translates as "raving ones". They were known as wild, insane women who could not be reasoned with. The mysteries of Dionysus inspired the women to ecstatic frenzy; they indulged in copious amounts of violence, bloodletting, sex and self-intoxication and mutilation. They were usually pictured as crowned with vine leaves, clothed in fawnskins and carrying the thyrsus, and dancing with the wild abandonment of complete union with primeval nature.

The Maenads were also known as Bassarids (or Bacchae or Bacchantes) in Roman mythology, after the penchant for the equivalent Roman god, Bacchus, to wear a fox-skin, a bassaris.

In Euripides' play, "The Bacchae", Theban Maenads murdered King Pentheus after he banned the worship of Bacchus because the Maenads denied Pentheus' divinity. Bacchus, Pentheus' cousin, himself lured Pentheus to the woods, where the Maenads tore him apart and his corpse was mutilated by his own mother, Agave.

A group of Maenads also killed Orpheus because they hated his music.

See also Icarius, Butes, Dryas, and Minyades for other examples of Dionysus inflicting insanity upon women as a curse.