irrational number


: a number that can be expressed as an infinite decimal with no set of consecutive digits repeating itself indefinitely and that cannot be expressed as the quotient of two integers

Examples of irrational number in a Sentence

Recent Examples on the Web Pi as a Rational Number So is there any number base in which pi is not an irrational number? Rhett Allain, WIRED, 14 Mar. 2024 The notion that raising an irrational number to multiple powers could result in a number with no numbers after the decimal point may seem far-fetched at first. Manon Bischoff, Scientific American, 24 Jan. 2024 His name is Techno Mechanicus Musk, but his parents call him Tau, for the irrational number. Jill Lepore, The New Yorker, 11 Sep. 2023 But instead the vectors had a ratio of the square root of 2—definitely an irrational number—showing that the polyiamond arrangements weren’t periodic. Manon Bischoff, Scientific American, 10 Apr. 2023 Pi is an irrational number. Ella Quittner, The New Yorker, 24 Nov. 2022 The most famous irrational number is pi. Kevin Fisher-Paulson, San Francisco Chronicle, 23 Mar. 2021 The irrational number is typically rounded down to 3.14 hence why the celebration takes place on March 14, which has a numerical date of 3/14. Amanda Pérez Pintado, USA TODAY, 14 Mar. 2023 For the math-averse, pi is an irrational number (as in can’t be represented by a fraction) used in geometry formulas, such as the area of a circle. Aaron Hutcherson, Washington Post, 13 Mar. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'irrational number.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1551, in the meaning defined above

Time Traveler
The first known use of irrational number was in 1551

Dictionary Entries Near irrational number

Cite this Entry

“Irrational number.” Dictionary, Merriam-Webster, Accessed 20 Apr. 2024.

Kids Definition

irrational number

: a number (as √͞ 2) that cannot be expressed as the quotient of two whole numbers

More from Merriam-Webster on irrational number

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