From Longman Dictionary of Contemporary Englishfallacyfal‧la‧cy /ˈfæləsi/ noun (plural fallacies) 1 [countable]WRONG/INCORRECT a false idea or belief, especially one that a lot of people believe is true SYN misconception It’s a common fallacy that a neutered dog will become fat and lazy.2 [countable, uncountable] formalMISTAKE a weakness in someone’s argument or ideas which is caused by a mistake in their thinking SYN flaw → pathetic fallacy
Examples from the Corpus
fallacy• However, the assumption that productivity must be directly related to biomass or chlorophyll is a fallacy.• It is a fallacy to think that the more information an organisation has the better will be the decisions.• It's a fallacy that all fat people are fat simply because they eat too much.• It was essentially a new attempt to revive the Burkeian fallacy of empire through freedom, obedience through liberty.• The idea that a good night's sleep will cure everything is a complete fallacy.• However, it is important immediately to dispose of one popular fallacy.• Don't believe the fallacy that money brings happiness.• This fallacy says that everything that can happen, will happen, given enough time.• This fallacy has snared philosophers from Plato to Leibniz and beyond, and it still snares many major physicists.• The error is in taking the polynomial to be a structural representation of the system, but the basic underlying fallacy remains.Origin fallacy (1400-1500) Latin fallacia, from fallere “to deceive” 