First Known Use: 14th century
Dictionary
lunatic
adjective lu·na·tic \ˈlü-nə-ˌtik\
Definition of LUNATIC
2
: wildly foolish <a lunatic idea>
— lunatic noun
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See lunatic defined for kids
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Origin 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
Related to LUNATIC
- Synonyms
- balmy, barmy [chiefly British], bats, batty, bedlam, bonkers, brainsick, bughouse [slang], certifiable, crackbrained, cracked, crackers, crackpot, cranky [dialect], crazed, crazy, cuckoo, daffy, daft, demented, deranged, fruity [slang], gaga, haywire, kooky (also kookie), loco [slang], loony (also looney), loony tunes (or looney tunes), insane, mad, maniacal (also maniac), mental, meshuga (or meshugge also meshugah or meshuggah), moonstruck, non compos mentis, nuts, nutty, psycho, psychotic, scatty [chiefly British], screwy, unbalanced, unhinged, unsound, wacko (also whacko), wacky (also whacky), wud [chiefly Scottish]
- Antonyms
- balanced, compos mentis, sane, sound, uncrazy
Other Psychology Terms
Rhymes with LUNATIC
bailiwick, biopic, Bolshevik, bone to pick, call in sick, candlestick, candlewick, cattle tick, cherry-pick, corner kick, Dominic, do the trick, double-quick, EBCDIC, fiddlestick, fingerpick, flutter kick, hemistich, heretic, Menshevik, meterstick, needlestick, onside kick, overtrick, point-and-click, politic, politick, polyptych, rhythm stick, scissors kick, shooting stick, singlestick, swagger stick, swizzle stick, taperstick, turn the trick, undertrick, walking stick, Watson-Crick
LUNATIC Defined for Kids
1lunatic
adjective lu·na·tic \ˈlü-nə-ˌtik\
Definition of LUNATIC for Kids
: insane 1
2lunatic
noun
Definition of LUNATIC for Kids
1
: an insane person
2
: a person who behaves very foolishly <That lunatic went through a red light.>
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