rational number


: a number that can be expressed as an integer or the quotient of an integer divided by a nonzero integer

Examples of rational number in a Sentence

Recent Examples on the Web Mathematically this is expressed by saying that, given an irrational number x, there are infinitely many rational numbers p/q such that |x - p/q| < 1/q^2, while for rational numbers there are only finitely many. Quanta Magazine, 13 Dec. 2023 Galois groups are mathematical objects that describe how entities called fields (like the real or rational numbers) change when they are extended with new elements. Kevin Hartnett, Quanta Magazine, 12 Oct. 2023 In particular, the three mathematicians prove the duality between periods and L-functions over number systems that arise in geometry called function fields, rather than over number fields — like the rational numbers — which are the true home of the Langlands program. Kevin Hartnett, Quanta Magazine, 12 Oct. 2023 The infinity of rational numbers is the same as the infinity of whole numbers. Quanta Magazine, 27 June 2023 Every rational number is algebraic, and some irrational numbers are too, like 3√2. Quanta Magazine, 27 June 2023 If the two new arrangements contained repeating patterns, the length of their translation vectors should have been related to each other—specifically, their ratio should have been a rational number. Manon Bischoff, Scientific American, 10 Apr. 2023 Bowen and Sabok’s proof is at its most elegant when all the colors involved appear frequently throughout the rational numbers. Leila Sloman, Quanta Magazine, 15 Mar. 2023 The polynomial can’t be solved using a rational number — a fraction made by dividing two integers. Quanta Magazine, 21 Apr. 2022 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'rational 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

1873, in the meaning defined above

Time Traveler
The first known use of rational number was in 1873

Dictionary Entries Near rational number

Cite this Entry

“Rational number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rational%20number. Accessed 2 Mar. 2024.

Kids Definition

rational number

: a number that can be expressed as a whole number or the quotient of two whole numbers

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