noun
illusion, misconception
Synonyms: aberration, ambiguity, artifice, bias, casuistry, cavil, deceit, deception, deceptiveness, delusion, deviation, elusion, equivocation, erratum, erroneousness, error, evasion, falsehood, faultiness, flaw, heresy, illogicality, inconsistency, inexactness, invalidity, misapprehension, miscalculation, misconstrual, misinterpretation, mistake, non sequitur, notion, paradox, perversion, preconception, prejudice, quibbling, quirk, solecism, sophism, sophistry, speciousness, subterfuge, untruth
Antonyms: certainty, evidence, fact, honesty, reality, right, surety, truth