noun hal·lu·ci·na·tion \ hə-ˌlü-sə-ˈnā-shən \
Updated on: 10 Nov 2017

Definition of hallucination

1 a :perception of objects with no reality usually arising from disorder of the nervous system or in response to drugs (such as LSD)
  • was having hallucinations
b :the object so perceived
  • wasn't sure if the rain was real or a hallucination
2 :an unfounded or mistaken impression or notion :delusion

Examples of hallucination in a Sentence

  1. He could not tell if what he was seeing was real or if it was a hallucination.

  2. He has been having hallucinations due to the medication.

Recent Examples of hallucination from the Web

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Origin and Etymology of hallucination

Synonym Discussion of hallucination

delusion, illusion, hallucination, mirage mean something that is believed to be true or real but that is actually false or unreal. delusion implies an inability to distinguish between what is real and what only seems to be real, often as the result of a disordered state of mind.
    • delusions of persecution
illusion implies a false ascribing of reality based on what one sees or imagines.
    • an illusion of safety
hallucination implies impressions that are the product of disordered senses, as because of mental illness or drugs.
    • suffered from terrifying hallucinations
mirage in its extended sense applies to an illusory vision, dream, hope, or aim.
    • claimed a balanced budget is a mirage

HALLUCINATION Defined for English Language Learners



Definition of hallucination for English Language Learners

  • : something (such as an image, a sound, or a smell) that seems real but does not really exist and that is usually caused by mental illness or the effect of a drug

HALLUCINATION Defined for Kids


noun hal·lu·ci·na·tion \ hə-ˌlü-sə-ˈnā-shən \

Definition of hallucination for Students

:the seeing of objects or the experiencing of feelings that are not real but are usually the result of mental disorder or the effect of a drug

Medical Dictionary


noun hal·lu·ci·na·tion \ hə-ˌlüs-ᵊn-ˈā-shən \

medical Definition of hallucination

1 :a perception of something (as a visual image or a sound) with no external cause usually arising from a disorder of the nervous system (as in delirium tremens or in functional psychosis without known neurological disease) or in response to drugs (as LSD) — compare delusion 2, illusion 2a
2 :the object of a hallucinatory perception

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