lunatic

lu-na-tic · noun

imported

Definitions

noun

  1. 1.

    (informal, often offensive) A person who is mentally ill or behaves in a wild, foolish manner.

  2. 2.

    Mentally ill; insane.

  3. 3.

    (historical) A person considered legally insane.

  4. 4.

    Extremely foolish or reckless.

Forms

plural: lunatics

Phrases & expressions

  • •
    lunatic fringe — the extreme or eccentric minority of a group
  • •
    lunatic asylum — (historical) a psychiatric hospital

Related words

Antonyms: sane person
See also: insane, lunar, madness
Synonyms: crazy person, madman, maniac

Etymology

From Old French lunatique, from Late Latin lunaticus ("moonstruck"), from Latin luna ("moon"). Based on the belief that the moon caused madness.