Lunatic
adj, noun ·Common ·High school level
Definitions
- 1 An insane person.
"While there are other races (or individuals—heaven forgive me, I am no ethnologist) who think you a criminal or a lunatic unless you carefully plod along from step to step like a hippopotamus out of water."
- 2 a reckless impetuous irresponsible person wordnet
- 3 an insane person wordnet
- 1 Crazed, mad, insane, demented.
- 2 Relating to the Moon; lunar. literary, rare
"As the narrator turns his attention to the moon itself and its Lunatic inhabitants, Heinsius seems to draw on the True History, but is still within the confines of the Icaromenippus."
- 3 Influenced or affected by the Moon. literary, rare
"This I remember: she was false as the lunatic sea."
- 1 insane and believed to be affected by the phases of the moon wordnet
Example
More examples"It has been said that a man at ten is an animal, at twenty a lunatic, at thirty a failure, at forty a fraud, and at fifty a criminal."
Etymology
From Middle English lunatik, from Old French lunatique, from Late Latin lunaticus (“moonstruck”), derived from Latin luna (“moon”), the connection stemming from the belief that changes of the moon caused intermittent insanity.
Related phrases
More for "lunatic"
Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.