hallucination has definitions from the fields of psychology,psychiatry
1
[ noun ] (psychology,psychiatry) illusory perception; a common symptom of severe mental disorder

Used in print

(Frank Oppenheimer, "Science and Fear-- A Discussion...)

Much of the former extreme uneasiness associated with visions and hallucinations and with death has disappeared .

2
[ noun ] an object perceived during a hallucinatory episode

Examples

"he refused to believe that the angel was a hallucination"

Related terms

object hallucinate

3
[ noun ] a mistaken or unfounded opinion or idea

Synonyms

delusion

Examples

"he has delusions of competence" "his dreams of vast wealth are a hallucination"

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