Lunatic is a term referring to a person who is seen as mentally ill, dangerous, foolish, [1] [2] or crazy—conditions once attributed to "lunacy". The word derives from lunaticus meaning "of the moon" or "moonstruck".

The meaning of LUNATIC is someone affected with a severely disordered state of mind. How to use lunatic in a sentence.

LUNATIC definition: 1. someone who behaves in a silly or dangerous way: 2. a word for a person who has a mental…. Learn more.

A lunatic is someone who is either clinically insane or just acting really crazy. Someone driving too fast and zigging in and out of traffic is driving like a lunatic.

What does the word lunatic mean? There are eight meanings listed in OED's entry for the word lunatic , one of which is labelled obsolete. See ‘Meaning & use’ for definitions, usage, and quotation evidence.

If you describe someone as a lunatic, you think they behave in a dangerous, stupid, or annoying way.

If you describe someone as a lunatic, you think they behave in a dangerous, stupid, or annoying way. [ informal , disapproval ] Her son thinks she's an absolute raving lunatic.

LUNATIC meaning: 1 : an insane person; 2 : a person who behaves in a very foolish way

a person whose actions and manner are marked by extreme eccentricity or recklessness. a person legally declared to be of unsound mind and who therefore is not held capable or …

A person who is affected by lunacy; a mentally deranged person. 2. A very foolish person. 1. Affected by lunacy; mentally deranged. 2. Of or for people who are mentally deranged. 3. Wildly or giddily foolish: a lunatic decision.