First Known Use: 14th century
Dictionary
fallacy
noun fal·la·cy \ˈfa-lə-sē\
: a wrong belief : a false or mistaken idea
: the quality of being false or wrong
plural fal·la·cies
Full Definition of FALLACY
2
a : a false or mistaken idea <popular fallacies> b : erroneous character : erroneousness
3
: an often plausible argument using false or invalid inference
See fallacy defined for English-language learners
See fallacy defined for kids
ADVERTISEMENT
Origin of FALLACY
Latin fallacia, from fallac-, fallax deceitful, from fallere to deceive
Related to FALLACY
- Synonyms
- delusion, error, falsehood, falsity, hallucination, illusion, misbelief, misconception, myth, old wives' tale, untruth
Other Logic Terms
Rhymes with FALLACY
FALLACIES Defined for Kids
fallacy
noun fal·la·cy \ˈfa-lə-sē\
plural fal·la·cies
Definition of FALLACY for Kids
1
: a false or mistaken idea
2
: false reasoning
Learn More About FALLACY
Browse
Next Word in the Dictionary: fallacy of accidentPrevious Word in the Dictionary: fallaciousAll Words Near: fallacy
ADVERTISEMENT
Seen & Heard
What made you want to look up fallacy? Please tell us where you read or heard it (including the quote, if possible).