il|lu|sion

il|lu|sion «ih LOO zhuhn», noun.

1. an appearance or feeling that misleads because it is not real; thing that deceives by giving a false idea; misleading appearance. The sides of a road give one an illusion of coming closer and closer together until they meet in the distance. »

The old man's ruddy complexion gave an illusion of good health. He [Clemenceau] had one illusion—France (Lord Keynes).

2. a false impression or perception: »

That slender snow-covered bush at the gate produced an illusion of a woman waiting there.

3. a false idea, notion, or belief; fancy: »

Many people have the illusion that wealth is the chief cause of happiness.

4. a delicate silk net or gauze, often used for veils and over wedding gowns: »

Wedding veils of French illusion are twisted into coronets (New Yorker).

5. Archaic. apparition; phantom: »

Stay, illusion! If thou hast any sound or use of voice, Speak to me (Shakespeare).

╂[< Latin illūsiō, -ōnis a mocking < illūdere to mock; see etym. under illude (Cf. ↑illude)]

Synonym Study 1 Illusion, delusion mean something mistakenly or falsely believed to be true or real. Illusion applies to something appearing to be real or true, but actually not existing or being quite different from what it seems: »

Good motion pictures create an illusion of reality.

Delusion applies to a false and often harmful belief about something that does exist: »

The old woman had the delusion that the butcher was always trying to cheat her.

Usage Illusion, allusion are sometimes confused. An illusion is a misleading appearance: »

an illusion of wealth.

An allusion is an indirect reference or slight mention: »

He made allusions to recent events without recounting them.