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fallacy

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noun fal·la·cy \ˈfa-lə-sē\

Simple Definition of fallacy

  • : a wrong belief : a false or mistaken idea

  • : the quality of being false or wrong

Full Definition of fallacy

plural fal·la·cies

  1. 1 a obsolete :  guile, trickery b :  deceptive appearance :  deception

  2. 2 a :  a false or mistaken idea <popular fallacies> b :  erroneous character :  erroneousness

  3. 3 :  an often plausible argument using false or invalid inference

Examples of fallacy

  1. The fallacy of their ideas about medicine soon became apparent.

  2. <the once-common fallacy that girls just weren't any good at math>



Origin of fallacy

Latin fallacia, from fallac-, fallax deceitful, from fallere to deceive


First Known Use: 14th century

Rhymes with fallacy



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