hallucinate
Americanverb (used without object)
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hallucinates,
present (3rd person singular)
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hallucinated,
past participle, past
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hallucinating
present participle
-
to see or hear things that do not exist outside the mind; have hallucinations.
People who ingested this fungus often hallucinated, seeing colored lights or hearing voices.
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Computers, Digital Technology. (of a machine learning program) to produce false information contrary to the intent of the user and present it as if true and factual.
verb (used with object)
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hallucinates,
present (3rd person singular)
-
hallucinated,
past participle, past
-
hallucinating
present participle
-
to see or hear (things that do not exist outside the mind); have hallucinations about.
In dramatic moments, the character hallucinates a very funny animated bear.
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Archaic. to affect with hallucinations.
verb
Other Word Forms
Derived Forms
Inflected Forms
Participles
Conjugated Forms
Present
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hallucinatesimple
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hallucinatessimple
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have hallucinatedperfect
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has hallucinatedperfect
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am hallucinatingprogressive
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are hallucinatingprogressive
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is hallucinatingprogressive
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have been hallucinatingperfect progressive
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has been hallucinatingperfect progressive
Past
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hallucinatedsimple
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had hallucinatedperfect
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was hallucinatingprogressive
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were hallucinatingprogressive
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had been hallucinatingperfect progressive
Future
Etymology
Origin of hallucinate
First recorded in 1595–1605; from Latin hallūcinātus “wandered mentally” past participle of hallūcinārī, variant of (h)ālūcinārī “to dream, talk idly, wander mentally”
Explanation
To hallucinate is to see or hear something that's not really there. If you hallucinate, it's a bit like dreaming while being awake. When someone hallucinates, what they're perceiving seems very real and vivid, although it's not. Many different things can cause a person to hallucinate, including drugs, mental illness, damage to the brain, and even lack of adequate sleep. Some people hallucinate regularly, if mildly, just as they're falling asleep at night. The original meaning of hallucinate was "deceive," from the Latin hallucinatus, "wander in the mind."
Vocabulary lists containing hallucinate
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
Generative AI systems are known for their ability to "hallucinate" and assert falsehoods as fact, even sometimes invent sources for inaccurate information.
From BBC ● Sep. 14, 2026
An automated healthcare agent that processes a routine prescription refill can’t afford to hallucinate so much as a single digit in a prescription number, lest the patient receive an incorrect medication with potentially harmful effects.
From The Wall Street Journal ● Jun. 25, 2026
But new research suggests there may be a more concerning issue emerging: humans can begin to "hallucinate with AI."
From Science Daily ● May 11, 2026
AI tools are known to hallucinate, or make up information.
From Los Angeles Times ● Apr. 14, 2026
My fever gets worse, and during one terrible evening I start to hallucinate.
From "Landscape with Invisible Hand" by M.T. Anderson
The fact that no one made it, that it’s the creation of a machine that hallucinates in exchange for electricity, only intensifies the sick, empty feeling the track leaves behind.
From Salon ● Aug. 6, 2026
If an agent hallucinates, Arcade can catch the error and correct it, allowing the workflow to continue, he said.
From The Wall Street Journal ● Jun. 15, 2026
"This means that visual information about things happening in the outside world becomes less accessible to our consciousness. To fill this gap in the puzzle, our brain inserts fragments from memory -- it hallucinates."
From Science Daily ● Feb. 15, 2026
What good is AI that analyzes financial data if it hallucinates numbers?
From MarketWatch ● Nov. 3, 2025
Sometimes Enrique hallucinates that someone is chasing him.
From "Enrique's Journey" by Sonia Nazario
Last year, a Los Angeles attorney was fined for submitting a filing full of legal citations that were hallucinated by ChatGPT.
From Los Angeles Times ● Mar. 18, 2026
It hallucinated that my actual finish was the same as the target finish time it originally predicted.
From The Wall Street Journal ● Nov. 3, 2025
One out of every five answers "contained major accuracy issues, including hallucinated details and outdated information."
From Barron's ● Oct. 21, 2025
Earlier this year, Apple suspended its Apple Intelligence news summary tool in the UK after it hallucinated false headlines and presented them as real news.
From BBC ● Mar. 20, 2025
In that state of hallucinated lucidity, not only did they see the images of their own dreams, but some saw the images dreamed by others.
From "One Hundred Years of Solitude" by Gabriel Garcia Marquez
His parents were told Riley was heading towards liver failure, and they watched as his condition deteriorated to the point where he was delirious and hallucinating.
From BBC ● Sep. 22, 2026
When generative AI systems give incorrect answers, people often describe the problem as AI "hallucinating at us," meaning the technology produces false information that users may mistakenly believe.
From Science Daily ● May 11, 2026
"This risk of a model making errors or hallucinating cannot be fully avoided in any technical way," said Munich Re's head of AI insurance, Michael von Gablenz.
From Barron's ● Mar. 15, 2026
I have yet to see any implementation of A.I. that I could consider either general-purpose or foundational, and I think it’s absurd to look at the hallucinating chatbots and inaccurate A.I.
From Slate ● Nov. 22, 2025
Sleep deprivation catches me and I start hallucinating.
From "Woodsong" by Gary Paulsen
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