To disillusion, disabuse, free from illusion.(verb)
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Use "disillusionize" in a sentence
"Punch and Judy show -- he is judged by the success of his imitation of life, and his own appearance will speedily disillusionize his public."
"In "The Lollard," when Miss Carey wants to disillusionize Angela, she does not sit down and argue her out of her insane infatuation for Fred; nor does she tell Angela that Fred is a "lollard" and weakly unmask him by describing his "lollard" points."
"She pictured Martha's shocked surprise at the very idea of staying in bed just for the fun of it, but she did not disillusionize Phyllis."