a positive integer or zero.
Origin of natural number
First recorded in 1755–65
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
any of the numbers 0,1,2,3,4,… that can be used to count the members of a set; the non-negative integers
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
A positive integer.
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