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rational number

American  

noun

Mathematics.

  1. a number that can be expressed exactly by a ratio of two integers.

rational number British  

noun

  1. any real number of the form a / b , where a and b are integers and b is not zero, as 7 or 7/3

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
rational number Scientific  

  1. A number that can be expressed as an integer or a quotient of integers. For example, 2, −5, and 1/2 are rational numbers.

Etymology

Origin of rational number

First recorded in 1900–05

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.