lunatic

play
adjective lu·na·tic \ˈlü-nə-ˌtik\

Definition of lunatic

  1. 1 dated a :  affected with a severely disordered state of mind :  insaneb :  designed for the care of mentally ill people a lunatic asylum

  2. 2 :  wildly foolish a lunatic idea lunatic behavior

lunatic

noun

Examples of lunatic in a Sentence

  1. He hatched a lunatic plot to overthrow the government.

  2. another of his lunatic ideas

Recent Examples of lunatic from the Web

These example sentences are collected from online sources. Help us improve them by sending feedback.

Origin and Etymology of lunatic

Middle English lunatik, from Anglo-French or Late Latin; Anglo-French lunatic, from Late Latin lunaticus, from Latin luna; from the belief that lunacy fluctuated with the phases of the moon


First Known Use: 14th century


LUNATIC Defined for Kids

1

lunatic

play
adjective lu·na·tic \ˈlü-nə-ˌtik\

Definition of lunatic for Students

  1. :  insane 1


2

lunatic

play
noun lu·na·tic

Definition of lunatic for Students

  1. 1 :  an insane person

  2. 2 :  a person who behaves very foolishly That lunatic went through a red light.


Medical Dictionary

lunatic

noun lu·na·tic

Medical Definition of lunatic

  1. :  an individual marked by a severely disordered state of mind


Law Dictionary

lunatic

noun lu·na·tic \ˈlü-nə-tik\

Legal Definition of lunatic

  1. :  an insane person —used especially formerly

lunatic

adjective


Seen and Heard

What made you want to look up lunatic? Please tell us where you read or heard it (including the quote, if possible).

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

WORD OF THE DAY

a small amount

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

  • winning-words-from-the-national-spelling-bee-logo
  • Which is the correct spelling of the winning word from 1988?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!