ILLUSION

n. 1 deception, delusion, fancy, misconception, misapprehension, fallacy, error, mistake, mistaken or false impression He is labouring under the illusion that he is a great pianist 2 fantasy, day-dream, hallucination, phantasm, phantom, chimera, phantasmagoria, mirage, aberration, vision, spectre, figment of the imagination, will-o'-the-wisp, ignis fatuus For years after he died, she had the illusion of seeing her father everywhere