hallucination
Americannoun
-
a sensory experience of something that does not exist outside the mind, caused by various physical and mental disorders, or by reaction to certain toxic substances, and usually manifested as visual or auditory images.
- Synonyms:
- aberration, phantasm
-
the sensation caused by a hallucinatory condition, or the object or scene visualized.
-
Computers, Digital Technology. (in the field of machine learning) false information generated by a machine learning program contrary to the intent of the user and presented as if it were true and factual.
noun
Usage
What is a hallucination? A hallucination is a sensory experience of something that does not actually exist and has no basis in reality. Hallucinations can be caused by mental disorders or toxic substances.A hallucination often takes the form of visual images or noises, as in Sangeet saw a hallucination of sparkling lights.Hallucination can also be used to refer to the sensation caused by one of these false sensory experiences, as in Roman was suffering from drug-induced hallucinations.More generally, hallucination can be used to mean a false notion or belief, as in His idea of what life was like in Canada was nothing more than a silly hallucination.Hallucination is similar to the words illusion and delusion, which also describe false beliefs or experiences. An illusion is a false image that is a result of a distortion or manipulation of actual things. For example, makeup can create the illusion that a person is younger than they actually are.A delusion is a persistent, false belief that may or may not be partially based on reality, as in The athlete’s huge ego constantly made him have delusions of being unbeatable.Example: The explorer suffered from terrifying hallucinations of ghosts and phantoms after eating the toxic mushrooms.
Related Words
See illusion.
Other Word Forms
- hallucinational adjective
- hallucinative adjective
- nonhallucination noun
Etymology
Origin of hallucination
First recorded in 1640–50; from Latin hallūcinātiōn-, stem of hallūcinātiō, variant of (h)ālūcinātiō, “a wandering of the mind”; hallucinate + -ion
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.
In custody, when asked whether he experienced hallucinations or voices, Calocane said "I do not want to discuss that with you", the inquiry heard.
From BBC
“Edda,” I introduced myself, wondering somehow if this was all really happening, or whether exhaustion from my travels was causing an elaborate hallucination.
From Literature
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The neuroscientist Anil Seth says the brain is a “prediction machine,” and selfhood a useful hallucination.
Companies in the AI race are striving to perfect the technology, but they have not eliminated the possibility of errors such as "hallucinations" in which fabricated output is confidently presented.
From Barron's
Unable to sleep after a traumatic birth in 2024, Lizzy quickly deteriorated into a state of psychosis - a potentially life-threatening condition that can cause hallucinations, severe insomnia and paranoia.
From BBC
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.