untrue

1 not being in agreement with what is true “the sky is purple” is an untrue statement Synonyms erroneous, inaccurate, incorrect, inexact, invalid, off, unsound, false, untruthful, wrongRelated Words counterfactual; specious, spurious; deceptive, delusive, delusory, distorted, fallacious, fictitious, illusory, misleading; amiss, askew, awry; deceitful, dishonest, fraudulent, lying, mendacious; unconfirmed, unproven, untested; fabricated, invented, made-up, trumped-upNear Antonyms confirmed, demonstrated, established, proven, tested; faultless, flawless, impeccable, letter-perfect, perfectAntonyms accurate, correct, errorless, exact, factual, precise, proper, right, sound, true, valid, veracious

2 not true in one's allegiance to someone or something untrue to his country in its time of need Synonyms disloyal, false, fickle, inconstant, perfidious, recreant, traitorous, treacherous, unfaithful, faithlessRelated Words irresponsible, trustless, undependable, unreliable, untrustworthy; faltering, hesitant, vacillating, wavering; dubious, irresolute, uncertain; apathetic, dispassionate, uninterestedNear Antonyms dependable, dutiful, reliable, responsible, solid, tried, tried-and-true, trustable, trustworthy, trusty; unfaltering, unhesitating, unwavering; determined, intent, resolute; confirmed, dyed-in-the-wool, inveterate, sworn; ardent, avid, enthusiastic, fervent, fervid, impassioned, passionateAntonyms constant, dedicated, devoted, devout, down-the-line, faithful, fast, loyal, staunch (also stanch), steadfast, steady, true