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 This equation is based on a tautology: the velocity of money is defined as the ratio of nominal GDP (real GDP times the price level) to the money supply. Alexander William Salter, National Review, 9 Apr. 2021 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, 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, 26 Apr. 2018 Profits have grown, but — contrary to Hassett’s simple tautology — wages have not followed. Jonathan Chait, Daily Intelligencer, 18 Apr. 2018 All the old political stagecraft and prevaricating, the Rumsfeldian tautologies — we’re way past that. Wesley Morris, New York Times, 24 Oct. 2017 Forgive the tautology, but such is the nature of what was once considered a premium position. Jack Wang, Orange County Register, 16 Apr. 2017 What’s more important is the ongoing tautology at the heart of the warrantless wiretapping controversy. Ryan Singel, WIRED, 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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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 20 Oct. 2021.

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More Definitions for tautology



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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