fallacy

delusion, error, falsehood, falsity, hallucination, illusion, misbelief, misconception, myth, old wives' tale, untruth

factoid; superstition; fiction, pretense ( pretence); distortion, inaccuracy, misapprehension, miscomprehension, misinterpretation, misjudgment, misperception, misunderstanding; misinformation, misknowledge, misreport, misrepresentation, misstatement; sophism, sophistry; fib, half-truth, lie, story, tale

erroneousness, fallaciousness, falsehood, falseness, falsity, untruth

speciousness, spuriousness; deception, deceptiveness, delusion; inaccuracy, incorrectness; dishonesty, mendaciousness, mendacity, untruthfulness

accuracy, actuality, correctness, factuality, factualness, genuineness; credibility, honesty, trustworthiness, truthfulness, veracity