To hear audio pronunciation of this topic, purchase a subscription or log in.

[L. hallucinari, to wander in one's mind]
A false perception having no relation to reality and not accounted for by any exterior stimulus. It is a dreamlike or nightmarish perception occurring while awake. It may be visual, esp. in medical illnesses or drug withdrawal syndromes; auditory, esp. in psychoses; tactile; gustatory; or olfactory. Affected patients typically appear confused and agitated and are unable to distinguish between the real and the imaginary.
SEE: delusion; SEE: illusion

There's more to see -- the rest of this topic is available only to subscribers.