tau·​tol·​o·​gy | \ tȯ-ˈtä-lə-jē How to pronounce tautology (audio) \
plural tautologies

Definition of tautology

1a : needless repetition of an idea, statement, or word Rhetorical repetition, tautology ('always and for ever'), banal metaphor, and short paragraphs are part of the jargon.— Philip Howard
b : an instance of such repetition The phrase "a beginner who has just started" is a tautology.
2 logic : a statement that is true by virtue of its logical form alone A logical combination of sentences that is always true, regardless of the truth or falsity of the constituent sentences, is known as a "tautology."— Rudy Rucker … now the objection was raised that the entire theory of natural selection rested on a tautology: "Who survives? The fittest. Who are the fittest? Those that survive."— Ernst Mayr

Examples of tautology in a Sentence

“A beginner who has just started” is a tautology.
Recent Examples on the Web Like the name of the lobbying group Leave Means Leave, the tautology suggests insecurity over the government’s commitment to honoring the referendum. Lionel Shriver, Harper's magazine, "No Exit," 10 Apr. 2019 Nowak and others claim that the general version of the formula is a tautology that can’t be tested empirically. Jordana Cepelewicz, Scientific American, "The Elusive Calculus of Insect Altruism," 26 Apr. 2018 Profits have grown, but — contrary to Hassett’s simple tautology — wages have not followed. Jonathan Chait, Daily Intelligencer, "Trump Economist Kevin Hassett: Tax Cuts Are Trickling Down to You," 18 Apr. 2018 All the old political stagecraft and prevaricating, the Rumsfeldian tautologies — we’re way past that. Wesley Morris, New York Times, "In These Lying Times, ‘Receipts’ Offer a Glimmer of Justice," 24 Oct. 2017 Forgive the tautology, but such is the nature of what was once considered a premium position. Jack Wang, Orange County Register, "2017 NFL draft position preview: Running backs," 16 Apr. 2017 What’s more important is the ongoing tautology at the heart of the warrantless wiretapping controversy. Ryan Singel, WIRED, "NYT Misses the Point: Administration Never Said It Wouldn’t Spy Without Warrants," 3 May 2007

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tautology.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of tautology

1566, in the meaning defined at sense 1a

History and Etymology for tautology

Late Latin tautologia, from Greek, from tautologos

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Time Traveler for tautology

Time Traveler

The first known use of tautology was in 1566

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Cite this Entry

“Tautology.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tautology. Accessed 8 Aug. 2020.

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More Definitions for tautology


How to pronounce tautology (audio)

English Language Learners Definition of tautology

: a statement in which you repeat a word, idea, etc., in a way that is not necessary

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More from Merriam-Webster on tautology

Thesaurus: All synonyms and antonyms for tautology

Rhyming Dictionary: Words that rhyme with tautology

Britannica.com: Encyclopedia article about tautology

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