nightmare

noun

A very unpleasant or frightening dream.

(figuratively) Any bad, miserable, difficult or terrifying situation or experience that arouses anxiety, terror, agony or great displeasure.

(now rare) A demon or monster, thought to plague people while they slept and cause a feeling of suffocation and terror during sleep.

(now chiefly historical) A feeling of extreme anxiety or suffocation experienced during sleep; sleep paralysis.

verb

(intransitive) To experience a nightmare.

(transitive) To imagine (someone or something) as in a nightmare.

(transitive) To trouble (someone or something), as by a nightmare.

Roots

mara-mare · Old English · goblin, incubus

Synonyms for nightmare

incubusn dreamn daydreamn bugbearn reverien bogeymann monstern

Synonyms & related words for nightmare

Find synonyms, related words, and the definition of nightmare — including incubus, dream, daydream, bugbear, reverie, bogeyman. Dendril is a free visual thesaurus that shows them on an interactive map where stronger matches sit closer to the center — no signup, no ads.

Words related to nightmare

Explore words related to nightmare — words associated with it, words that go with it, and its nearest matches in meaning. Related words include nightmarish, hagride, sweven, woolgather, dreamland, dreamlike, horrification, hellish. Click any word to make it the center of the map and keep exploring the web of connections.

Synonyms for nightmare

Common synonyms for nightmare include incubus, dream, daydream, bugbear, reverie, bogeyman, monster — words that share a close meaning. Hover or tap any word on the map for its definition and part of speech.

Where does nightmare come from?

The word nightmare breaks down into one root of Old English origin: the root -mare, from Old English mara (“goblin, incubus”). Explore each root to see other English words built from the same source.