To disillusion means to cause someone to realize that a belief or ideal they had was false.(verb)
An example of disillusion is when you tell a small child that Santa isn't real.
Disillusion is defined as disappointment that you feel when you realize something you thought was true wasn't, or when you realize that something you thought was good is not as good as you believed it was.(noun)
An example of disillusion is what you feel when you find out that Santa isn't real.
See disillusion in Webster's New World College Dictionary
See disillusion in American Heritage Dictionary 4
transitive verb dis·il·lu·sioned, dis·il·lu·sion·ing, dis·il·lu·sions
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