tautology

noun

tau·​tol·​o·​gy tȯ-ˈtä-lə-jē How to pronounce tautology (audio)
plural tautologies
1
a
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
That tautology, in the age of Trump, is now a matter of judicial precedent. Megan Garber, The Atlantic, 29 Apr. 2025 Saying ‘Hungary is for Hungarians’ or ‘America is for Americans’ is a tautology. Andrew Marantz, New Yorker, 28 Apr. 2025 Sadaf spouts a tautology — faith as faith — that also holds for patriotism. Armond White, National Review, 22 Jan. 2025 Yes, a win is a win, but tautologies aside, for the Niners, a win with Purdy playing like one of the finest quarterbacks in the NFL on Sunday would speak volumes. Dieter Kurtenbach, The Mercury News, 25 Oct. 2024 The goal was to market something in every category, which led to the occasional tautology. Andrew Cockburn, Harper's Magazine, 22 Aug. 2024

Word History

Etymology

Late Latin tautologia, from Greek, from tautologos

First Known Use

1566, in the meaning defined at sense 1a

Time Traveler
The first known use of tautology was in 1566

Browse Nearby Words

Cite this Entry

“Tautology.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tautology. Accessed 11 Sep. 2025.

Kids Definition

tautology

noun
tau·​tol·​o·​gy tȯ-ˈtäl-ə-jē How to pronounce tautology (audio)
plural tautologies
: needless repetition of an idea, statement, or word
also : an instance of such repetition
"a beginner who has just started" is a tautology
tautological
ˌtȯt-ᵊl-ˈäj-i-kəl
adjective

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