Definition of illusion

• n. - An unreal image presented to the bodily or mental vision; a deceptive appearance; a false show; mockery; hallucination.
• n. - Hence: Anything agreeably fascinating and charning; enchantment; witchery; glamour.
• n. - A sensation originated by some external object, but so modified as in any way to lead to an erroneous perception; as when the rolling of a wagon is mistaken for thunder.
• n. - A plain, delicate lace, usually of silk, used for veils, scarfs, dresses, etc.