The definition of an illusion is an idea or something you can see that isn’t real.(noun)
An example of an illusion is a magician making someone disappear in a box.
Illusion is defined as something that tricks the eye.(noun)
An example of an illusion is a drawing that can look like an old lady or a vase depending on which part you focus on.
See illusion in Webster's New World College Dictionary
Origin: ME illusioun < OFr illusion < L illusio, a mocking (in LL(Ec), deceit, illusion) < illusus, pp. of illudere, to mock, play with < in-, on + ludere, to play: see ludicrous
See illusion in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French
Origin: , from Late Latin illūsiō, illūsiōn-
Origin: , from Latin, a mocking, irony
Origin: , from illūsus
Origin: , past participle of illūdere, to mock
Origin: : in-, against; see in-2
Origin: + lūdere, to play; see leid- in Indo-European roots.
top: In a Hering figure, straight horizontal rules appear curved.
bottom: In Gestalt theory boxes, a gray box against a black background appears lighter than the same gray box against a white background.
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