Medical Dictionary


noun il·lu·sion \il-ˈü-zhən\

Medical Definition of ILLUSION

:  a misleading image presented as a visual stimulus
a :  perception of something objectively existing in such a way as to cause misinterpretation of its actual nature; especially :  optical illusion—compare delusion 2 b :  hallucination 1 c :  a pattern capable of reversible perspective
il·lu·sion·al \-ˈüzh-nəl, -ən-əl\ adjective
How to use a word that (literally) drives some people nuts.
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