Adjacent Words

Fallacy definitions

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Webster's 1828 Dictionary

FAL'LACY, n. [L. fallacia.]
1. Deceptive or false appearance; deceitfulness; that which misleads the eye or the mind. Detect the fallacy of the argument.
2. Deception; mistake. This appearance may be all a fallacy.
I'll entertain the favored fallacy.

WordNet (r) 3.0 (2005)

n
1: a misconception resulting from incorrect reasoning [syn: fallacy, false belief]

Merriam Webster's

noun (plural -cies) Etymology: Latin fallacia, from fallac-, fallax deceitful, from fallere to deceive Date: 14th century 1. a. obsolete guile, trickery b. deceptive appearance ; deception 2. a. a false or mistaken idea <popular fallacies> b. erroneous character ; erroneousness 3. an often plausible argument using false or invalid inference

Oxford Reference Dictionary

n. (pl. -ies) 1 a mistaken belief, esp. based on unsound argument. 2 faulty reasoning; misleading or unsound argument. 3 Logic a flaw that vitiates an argument. Derivatives: fallacious adj. fallaciously adv. fallaciousness n. Etymology: L fallacia f. fallax -acis deceiving f. fallere deceive

Webster's 1913 Dictionary

Fallacy Fal"la*cy, n.; pl. Fallacies. [OE. fallace, fallas, deception, F. fallace, fr. L. fallacia, fr. fallax deceitful, deceptive, fr. fallere to deceive. See Fail.] 1. Deceptive or false appearance; deceitfulness; that which misleads the eye or the mind; deception. Winning by conquest what the first man lost, By fallacy surprised. --Milton. 2. (Logic) An argument, or apparent argument, which professes to be decisive of the matter at issue, while in reality it is not; a sophism. Syn: Deception; deceit; mistake. Usage: Fallacy, Sophistry. A fallacy is an argument which professes to be decisive, but in reality is not; sophistry is also false reasoning, but of so specious and subtle a kind as to render it difficult to expose its fallacy. Many fallacies are obvious, but the evil of sophistry lies in its consummate art. ``Men are apt to suffer their minds to be misled by fallacies which gratify their passions. Many persons have obscured and confounded the nature of things by their wretched sophistry; though an act be never so sinful, they will strip it of its guilt.'' --South.

Collin's Cobuild Dictionary

(fallacies) A fallacy is an idea which many people believe to be true, but which is in fact false because it is based on incorrect information or reasoning. It's a fallacy that the affluent give relatively more to charity than the less prosperous... N-VAR: oft N that, N of n/-ing

Soule's Dictionary of English Synonyms

n. 1. Illusion, deception, deceit, delusion, mistake, error, misconception, misapprehension. 2. Sophism, paralogism, sophistry, deceitful or worthless argument.

Moby Thesaurus

Albigensianism, Arianism, Catharism, Ebionitism, Erastianism, Gnosticism, Jovinianism, Lollardy, Manichaeanism, Manichaeism, Monophysism, Monophysitism, Pelagianism, Waldensianism, Wyclifism, aberrancy, aberration, antinomianism, apparent soundness, argument, argument by analogy, argumentum ad baculum, argumentum ad captandum, argumentum ad hominem, bad case, bamboozlement, befooling, begging the question, bluffing, calculated deception, casuistry, circular argument, circularity, circumvention, claptrap, conning, crowd-pleasing argument, deceiving, deception, deceptiveness, defectiveness, defrauding, delusion, delusiveness, deviancy, disingenuousness, distortion, dupery, elusion, emanatism, empty words, enmeshment, ensnarement, entanglement, entrapment, equivocalness, equivocation, errancy, erroneousness, error, evasion, evasive reasoning, fallaciousness, false doctrine, falsehood, falseness, falsity, fault, faultiness, flaw, flawedness, flimflam, flimflammery, fond illusion, fooling, formal fallacy, hallucination, hamartia, heresy, heterodoxy, hoodwinking, hylotheism, hysteron proteron, illusion, inconsistency, insincere argument, insincerity, inveracity, jesuitism, jesuitry, kidding, logical fallacy, material fallacy, mere rhetoric, mirage, misapplication, misbelief, miscalculation, misconception, misconstruction, misdoing, misfeasance, misinterpretation, misjudgment, mistake, misunderstanding, moonshine, mystification, non sequitur, obfuscation, obscurantism, outwitting, overreaching, oversubtlety, pantheism, paralogism, peccancy, perversion, petitio principii, phantasm, philosophism, plausibility, plausibleness, pseudosyllogism, putting on, quibble, rationalization, self-contradiction, self-deception, sin, sinfulness, snow job, solecism, song and dance, sophism, sophistical reasoning, sophistication, sophistry, special pleading, speciosity, specious reasoning, speciousness, spoofery, spoofing, spuriousness, subterfuge, subtlety, swindling, trickiness, tricking, truthlessness, unorthodoxy, untrueness, untruth, untruthfulness, verbal fallacy, vicious circle, vicious reasoning, victimization, vision, weak point, willful misconception, wishful thinking, wrong, wrongness