tautology

noun

tau·​tol·​o·​gy tȯ-ˈtä-lə-jē 

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

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

In this tautology, the act of spending is proof that the spending is justified. —Matteo Wong, The Atlantic, 17 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

In other words, the industry is asking the world to engage in something like a trillion-dollar tautology: AI’s world-transformative potential justifies spending any amount of resources, because its evangelists will spend any amount to make AI transform the world. —Matteo Wong, The Atlantic, 29 July 2024

In his world view, doomed romanticism isn’t an oxymoron but a tautology: to experience love deep within one’s bones comes at the cost of one’s earthly comforts and worldly aspirations, even one’s life. —Richard Brody, The New Yorker, 17 Apr. 2024

At first, the subjective theory might be misunderstood as a tautology – market goods are worth what people will pay for them. —Dave Birnbaum, Forbes, 19 Feb. 2024

Too often, analysts of these anticorruption drives fall into a tautology, assuming that anyone purged for graft by an autocrat must have been an enemy of the autocrat to begin with—otherwise, why would they have been purged? —Andrew Leber, Foreign Affairs, 15 Nov. 2017

Which is a tautology. —Patrick Skerrett, STAT, 3 Mar. 2023

Word History

Etymology

Late Latin tautologia, from Greek, from tautologos

First Known Use

1566, in the meaning defined at sense 1a

Kids Definition

tautology

noun

tau·​tol·​o·​gy tȯ-ˈtäl-ə-jē 

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