falsehood

1 a false idea or belief the possibility of a perpetual motion machine is one falsehood that has been disproved by modern physics Synonyms delusion, error, fallacy, falsity, hallucination, illusion, misbelief, misconception, myth, old wives' tale, untruthRelated Words factoid; superstition; fiction, pretense (or pretence); distortion, inaccuracy, misapprehension, miscomprehension, misinterpretation, misjudgment, misperception, misunderstanding; misinformation, misknowledge, misreport, misrepresentation, misstatement; sophism, sophistry; fib, half-truth, lie, story, taleAntonyms truth, verity

2 a statement known by its maker to be untrue and made in order to deceive several falsehoods in the witness's testimony that may be grounds for perjury Synonyms fable, fabrication, fairy tale, lie, falsity, fib, mendacity, prevarication, story, tale, taradiddle (or tarradiddle), untruth, whopperRelated Words distortion, exaggeration, half-truth; ambiguity, equivocation, obliquity; defamation, libel, slander; perjury; bluff, fiction, pose, pretense (or pretence); humbug, jive, nonsense; canard, fallacy, misconception, myth; falsification, misinformation, misreport, misrepresentation, misstatement; deceit, deceitfulness, dishonesty, duplicity, fraudulenceNear Antonyms fact, truism, verity; honesty, truthfulness, veracity; authentication, confirmation, substantiation, validation, verificationAntonyms truth

3 the quality or state of being false scientists eventually demonstrated the falsehood of the claim that prehistoric fish did not evolve lungs and legs Synonyms erroneousness, fallaciousness, fallacy, falseness, falsity, untruthRelated Words speciousness, spuriousness; deception, deceptiveness, delusion; inaccuracy, incorrectness; dishonesty, mendaciousness, mendacity, untruthfulnessNear Antonyms accuracy, actuality, correctness, factuality, factualness, genuineness; credibility, honesty, trustworthiness, truthfulness, veracityAntonyms truth, verity

4 the tendency to tell lies a cynic who believes that politics are a veritable fount of falsehood Synonyms deceit, deceitfulness, dishonesty, mendaciousness, mendacity, untruthfulnessRelated Words artifice, craft, craftiness, crookedness, cunning, dissembling, dissimulation, double-dealing, duplicity, fakery, foxiness, guile, guilefulness, insincerity, trickishness, wiliness; falseness; hypocrisyNear Antonyms honor, incorruptibility; candidness, candor, frankness, good faith, plainspokenness, sincerity, straightforwardness; dependability, reliability, reliableness, trustworthiness; accuracy, objectivity; authenticity, correctness, genuineness; credibilityAntonyms honesty, integrity, probity, truthfulness, veraciousness, veracity, verity