What does "lunatic" mean?

Lunatic: Of or pertaining to, or suitable for, an insane person; evincing lunacy; as, lunatic gibberish; a lunatic asylum.

Additional senses

  1. 2.A person affected by lunacy; an insane person, esp. one who has lucid intervals; a madman; a person of unsound mind. The lunatic, the lover, and the poet, Are of imagination all compact. Shak.

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