lunatic

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.

The root of this word is luna, which means moon. That's because lunatic originally meant someone who went crazy with every phase of the moon, kind of like a werewolf. Most people these days don't believe in moon-caused insanity, but we still talk about lunatics, sometimes meaning clinically insane people. More often this is a slang term, used mainly in exaggerations, for anyone who seems wild and out of control.

Definitions of lunatic
1

n an insane person

Synonyms:
madman, maniac
Types:
show 4 types...
hide 4 types...
crazy, looney, loony, nutcase, weirdo
someone deranged and possibly dangerous
bedlamite
an archaic term for a lunatic
pyromaniac
a person with a mania for setting things on fire
madwoman
a woman lunatic
Type of:
diseased person, sick person, sufferer
a person suffering from an illness

n a reckless impetuous irresponsible person

Synonyms:
daredevil, harum-scarum, hothead, madcap, swashbuckler
Types:
tearaway
a reckless and impetuous person
Type of:
adventurer, venturer
a person who enjoys taking risks

adj insane and believed to be affected by the phases of the moon

Synonyms:
moonstruck
insane
afflicted with or characteristic of mental derangement

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