Lunatic definition from WIKI

http://en.wikipedia.org/wiki/Lunatic

Lunatic

From Wikipedia, the free encyclopedia

For other uses, see Lunatic (disambiguation).

"Loony" redirects here. For the Canadian 1 dollar coin (loonie), see Canadian 1 dollar coin. Or see Looney (disambiguation) or Luni (disambiguation).

"Lunatic" is an informal term referring to people who are considered mentally ill, dangerous, foolish or unpredictable; conditions once called lunacy. The term may be considered insulting in serious contexts, though is sometimes used in friendly jest. The word derives from lunaticus meaning "of the moon" or "moonstruck".