noun
hallucination
huh-loo-sih-NAY-shuhn
noun
1
A false perception of something that isn't really there, often caused by illness, drugs, or extreme stress.
"The patient reported vivid hallucinations during the night."
"Sleep deprivation can trigger mild hallucinations."
2
A confidently stated but false piece of information generated by an AI system.
"The report contained an AI hallucination — a fake statistic with no real source."
How to Use Hallucination
Learner’s notesIn plain EnglishSomething perceived — or, for AI, generated — that isn't actually real or true.
Common pairings
have a hallucination
AI hallucination
Word Forms
hallucinations plural
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The patient reported vivid _____ during the night.
Etymology
From the verb hallucinate, ultimately from Latin hallucinatus.