hallucinate

verb

hal·​lu·​ci·​nate hə-ˈlü-sə-ˌnāt How to pronounce hallucinate (audio)
hallucinated; hallucinating
Synonyms of hallucinatenext

transitive verb

1
: to affect with visions or imaginary perceptions
2
: to perceive or experience as a hallucination

intransitive verb

: to have hallucinations
hallucinator
hə-ˈlü-sə-ˌnā-tər How to pronounce hallucinate (audio)
noun

Examples of hallucinate in a Sentence

The patient may hallucinate if she has a fever.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
So what if the compass hallucinates half the time? — Caroline Rose Giuliani, New Yorker, 19 May 2026 But hallucinated references in real studies produced by humans could be just as widespread, and potentially even harder to track down. — Tristan Bove, Fortune, 24 May 2026 The underlying technology uses sixteen years of structured mapping, global returns data, and garment construction expertise to prevent system lag and hallucinated recommendations on high-traffic shopping days. — Arthur Zaczkiewicz, Footwear News, 26 May 2026 Without a unified, clean, and accessible data structure, AI outputs quickly become ambiguous, hallucinated, and diluted, deepening the clarity crisis rather than resolving it. — Ali Hoss, Forbes.com, 30 June 2026 See All Example Sentences for hallucinate

Word History

Etymology

Latin hallucinatus, past participle of hallucinari, allucinari to prate, dream, modification of Greek alyein to be distressed, to wander

First Known Use

circa 1834, in the meaning defined at transitive sense 1

Time Traveler
The first known use of hallucinate was circa 1834

Browse Nearby Words

hall tree
hallucinate
hallucination
See all Nearby Words

Cite this Entry

“Hallucinate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hallucinate. Accessed 7 Jul. 2026.

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Kids Definition

hallucinate

verb
hal·​lu·​ci·​nate hə-ˈlüs-ə-ˌnāt How to pronounce hallucinate (audio)
hallucinated; hallucinating
: to have hallucinations or experience as a hallucination

Medical Definition

hallucinate

verb
hal·​lu·​ci·​nate hə-ˈlüs-ᵊn-ˌāt How to pronounce hallucinate (audio)
hallucinated; hallucinating

transitive verb

1
: to affect with visions or imaginary perceptions
the patient is not hallucinated
2
: to perceive or experience as a hallucination
may hallucinate monsters or attackers—M. J. Horowitz

intransitive verb

: to have hallucinations

More from Merriam-Webster on hallucinate

Thesaurus: All synonyms and antonyms for hallucinate

Nglish: Translation of hallucinate for Spanish Speakers

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