Definition of hallucination
1a : a sensory perception (such as a visual image or a sound) that occurs in the absence of an actual external stimulus and usually arises from neurological disturbance (such as that associated with delirium tremens, schizophrenia, Parkinson's disease, or narcolepsy) or in response to drugs (such as LSD or phencyclidine)
visual/auditory/olfactory/gustatory/tactile hallucinations a drug-induced hallucination An important aspect of the study of hallucinations is the judgement of reality. How does a patient confer the character of reality on stimuli which, beyond any reasonable doubt, originate in his own mind?— Cesare Davalli et al.
b : the object of a hallucinatory perception
wasn't sure if the creature was real or a hallucination
2 : an unfounded or mistaken impression or notion : delusion
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Time Traveler for hallucination
The first known use of hallucination was in 1629
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