hallucination

[ huh-loo-suh-ney-shuhn ]

noun

1. 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

2. the sensation caused by a hallucinatory condition, or the object or scene visualized.
3. a false notion, belief, or impression; illusion; delusion.
4. 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.

hallucination

/ həˌluːsɪˈneɪʃən /

noun

1. the alleged perception of an object when no object is present, occurring under hypnosis, in some mental disorders, etc

hallucination

1. A false perception that appears to be real, as when, for example, a man dying of thirst in a desert thinks that he sees a lake. ( See also delusion .)

Derived Forms

• halˌluciˈnational, adjective

Other Words From

• hal·lu·ci·na·tion·al hal·lu·ci·na·tive [h, uh, -, loo, -s, uh, -ney-tiv, -n, uh, -tiv], adjective
• non·hal·lu·ci·na·tion noun

Word History and Origins

Origin of hallucination¹

First recorded in 1640–50; from Latin hallūcinātiōn-, stem of hallūcinātiō, variant of (h)ālūcinātiō, “a wandering of the mind”; hallucinate + -ion

Synonym Study

See illusion.

Example Sentences

All the weirdness of LSD—the hallucinations and acid insights and everything else—may be a direct consequence of this biochemical blockade of serotonin release.

From Nautilus

About an hour after Clifford Howard consumed three buttons of peyote, the hallucinations kicked in.

From Washington Post

Vision without execution is hallucination, but execution without vision is like a hamster wheel.

From Ozy

These are less noticeable than the so-called positive symptoms, which indicate the presence of something extra, such as hallucinations.

From MIT Technology Review

They don’t mention these auditory hallucinations explicitly, but they do use associated words—“sound,” “hear,” “chant,” “loud”—more often in regular conversation.

From MIT Technology Review

How can we taxonomize their experience, and differentiate it from hallucination, or psychotic break?

From The Daily Beast

The hallucination is visually incoherent, either a rough approximation of text or a random assemblage of letters.

From The Daily Beast

It's confusing at times; what's real and what's a hallucination isn't always clear.

From The Daily Beast

But this is yet another hallucination, because, in fact, they don't.

From The Daily Beast

The whole thing is played completely straight, with no sign that it is a dream sequence, hallucination, or break from reality.

From The Daily Beast

The little maid calls him Drac, identifies the flower in his hand, and lives on in this hallucination.

From Project Gutenberg

But even this great marvel seemed natural in comparison with the singular hallucination to which I was presently subjected.

From Project Gutenberg

I questioned him more fully than I had ever done, with a view to making myself master of the facts of his hallucination.

From Project Gutenberg

She had a sentimental hallucination as other people have a physical one.

From Project Gutenberg

It seems as if the young man was under the hallucination of his fever?

From Project Gutenberg

Related Words

• illusion
• phantom

More About Hallucination

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.

Where does hallucination come from?

The first records of the term hallucination come from around 1640. It ultimately comes from the Latin (h)allūcinātiō, meaning “a wandering of the mind.” Hallucinations are produced entirely by a person’s mind and are not based on anything actually happening outside of it.

Hallucinations are often caused by toxic substances, such as mushrooms, or mental disorders such as schizophrenia. Some of the most common types of hallucinations include feeling like something is crawling on your skin, hearing sounds or voices, or seeing lights or patterns.

Did you know … ?

What are some other forms related to hallucination?

• nonhallucination (noun)
• hallucinational (adjective)
• hallucinative (adjective)
• hallucinatory (adjective)

What are some synonyms for hallucination?

• phantom
• aberration
• apparition

What are some words that share a root or word element with hallucination?

• hallucinate
• hallucinogen
• hallucinosis

What are some words that often get used in discussing hallucination?

• mental disorder
• toxic
• under the influence

What are some words hallucination may be commonly confused with?

• illusion
• delusion

How is hallucination used in real life?

Many people experience hallucinations, and they are commonly depicted in works of popular culture.

Took a hike on an empty road where, I swear, I was passed by a 1938 Rolls Royce Wraith. I can't decide if it was a hallucination, time travel, or an actual ghost.

— Meg Gardiner (@MegGardiner1) April 2, 2020

I'm actually seeing hallucinations.. Like I swear to god I just saw a talking pillow

— Rachel Levin (@rclbeauty101) May 7, 2013

Try using hallucination!

Is hallucination used correctly in the following sentence?

The sailor was deceived by the sea monster’s hallucination, which made it appear as a beautiful mermaid.