n. pl. fal·la·cies
1. A false notion.
2. A statement or an argument based on a false or invalid inference.
3. Incorrectness of reasoning or belief; erroneousness.
4. The quality of being deceptive.
[Alteration of Middle English fallace, from Old French, from Latin fallācia, deceit, from fallāx, fallāc-, deceitful, from fallere, to deceive.]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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