Simple Definition of nightmare
: a dream that frightens a sleeping person : a very bad dream
: a very bad or frightening experience or situation
Full Definition of nightmare
1 : an evil spirit formerly thought to oppress people during sleep
2 : a frightening dream that usually awakens the sleeper
3 : something (as an experience, situation, or object) having the monstrous character of a nightmare or producing a feeling of anxiety or terror
Examples of nightmare
Mommy, I had a really scary nightmare.
The party was a complete nightmare.
Origin of nightmare
Middle English, from 1night + 1mare
First Known Use: 14th century
Rhymes with nightmare
affair, aglare, airfare, Ajmer, Altair, antbear, armchair, au pair, aware, bakeware, barware, Basseterre, Baudelaire, beachwear, bergère, beware, bid fair, big hair, black bear, bricklayer, broodmare, brown bear, bugbear, caneware, carfare, Carrère, cave bear, chi-square, clayware, club chair, compare, compere, confrere, cookware, corsair, courseware, creamware, crosshair, cudbear, daymare, dead air, decare, deck chair, declare, delftware, despair, dishware, éclair, elsewhere, ensnare, eyewear, fanfare, fieldfare, firmware, flatware, Flaubert, footwear, forbear, forebear, forswear, foursquare, freeware, funfair, galère, giftware, glassware, Great Bear, groupware, Gruyère, guard hair, hardware, health care, hectare, high chair, horsehair, hot air, impair, infare, Khmer, Kildare, knitwear, life-care, light air, longhair, loungewear, Mayfair, menswear, meunière, midair, mohair, Molière, neckwear, no fair, outstare, out-there, outwear, playwear, plein air, plowshare, Poor Clare, Port Blair, portiere, premiere, prepare, pushchair, rainwear, redware, repair, root hair, Sancerre, sea hare, shank's mare, shareware, shorthair, side chair, Sinclair, skiwear, sleepwear, slipware, sloth bear, software, somewhere, spongeware, sportswear, stemware, stoneware, sun bear, swimwear, threadbare, tinware, torchère, trouvère, tuyere, unfair, unhair, unswear, Voltaire, warfare, welfare, wheelchair, wirehair, workfare
Medical Definition of nightmare
: a frightening or distressing dream that usually awakens the sleeper
Learn More about nightmare
Thesaurus: All synonyms and antonyms for "nightmare" Medical Dictionary: Definition of "nightmare" Spanish Central: Translation of "nightmare" Nglish: Translation of "nightmare" for Spanish speakers Britannica English: Translation of "nightmare" for Arabic speakers Britannica.com: Encyclopedia article about "nightmare"
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