Merriam-Webster's Dictionary and Thesaurus - Merriam-Webster [499]
false adjective fals·er; fals·est 1 : not genuine : artificially made or assumed
2 : intentionally untrue
3 : adjusted or made so as to deceive <~ scales>
4 a : tending to mislead : DECEPTIVE <~ promises>
b : assumed or designed to deceive
5 : not true <~ concepts>
6 : not faithful or loyal : TREACHEROUS
7 : not essential or permanent <~ front>
8 : inaccurate in pitch
9 : based on mistaken ideas
— false·ly adverb
Synonyms
[1] artificial, bogus, fake, imitation, mechanical, mock, phony, sham, synthetic, unnatural
[3, 4b] counterfeit, crooked, deceitful, dishonest, fraudulent, phony, sham, spurious
[4a] deceitful, deceptive, misleading, specious—more at DECEPTIVE
[5] erroneous, inaccurate, incorrect, inexact, untrue, wrong
Antonyms
accurate, correct, right, sound, true
[6] disloyal, faithless, traitorous, treacherous, unfaithful
false·hood noun 1 : something that is untrue; especially : an untrue statement : LIE
2 : absence of truth or accuracy
3 : the practice of lying
Synonyms
error, fallacy, falsity, illusion, misconception, myth, old wives' tale, untruth—more at FALLACY
fabrication, fairy tale, falsity, fib, lie, mendacity, prevarication, story, tale, untruth, whopper—more at LIE
false·ness noun 1 : the quality or state of being false
2 : an instance of treachery : an act of perfidy or treason
Synonyms
[1] fallacy, falsity, untruth
[2] betrayal, disloyalty, infidelity, perfidy, treachery, treason, unfaithfulness—more at BETRAYAL
fal·set·to noun, plural -tos [ORIGIN: It, fr. dim. of falso false]
: an artificially high voice; especially : an artificial singing voice that overlaps and extends above the range of the full voice esp. of a tenor
fal·si·fy verb -fied; -fy·ing 1 : to prove to be false
2 : to alter so as to deceive
3 : LIE; also : MISREPRESENT
— fal·si·fi·able adjective
— fal·si·fi·ca·tion noun
Synonyms
color, distort, garble, misinterpret, misrepresent, misstate, pervert, twist, warp—more at GARBLE
fal·si·ty noun 1 : something false
2 : the quality or state of being false
Synonyms
[1] fallacy, falsehood, fib, lie, myth, tale, untruth
[2] betrayal, disloyalty, infidelity, perfidy, treachery, treason, unfaithfulness—more at BETRAYAL
fal·ter verb 1 : to move unsteadily : TOTTER
2 : to hesitate in speech : STAMMER
3 : to hesitate in purpose or action : WAVER