ordinal number

noun

1

: a number designating the place (such as first, second, or third) occupied by an item in an ordered sequence see Table of Numbers

2

: a number assigned to an ordered set that designates both the order of its elements and its cardinal number

Examples of ordinal number in a Sentence

Recent Examples on the Web

Interestingly enough, Kruskal's tree theorem required non-finite mathmatics to prove, using advanced techniques such as transfinite arithmetic and ordinal numbers. —Jay Bennett, Popular Mechanics, 20 Oct. 2017

Word History

First Known Use

1607, in the meaning defined at sense 1

Kids Definition

ordinal number

noun

: a number indicating the place (as first, fifth, 22nd) of an item in an ordered sequence compare cardinal number see number