rational number

noun

: 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
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Assuming that the lengths of the triangle correspond to rational numbers, and are integers and have no common divisor—or so everyone thought. Manon Bischoff, Scientific American, 13 June 2024 Elliptic curves restricted to the rational numbers — numbers that can be written as fractions — are particularly useful. Lyndie Chiou, Quanta Magazine, 5 Mar. 2024

Word History

First Known Use

1873, in the meaning defined above

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

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Cite this Entry

“Rational number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rational%20number. Accessed 9 Sep. 2025.

Kids Definition

rational number

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

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