cardinal number


Definition of cardinal number

1 : a number (such as 1, 5, 15) that is used in simple counting and that indicates how many elements there are in an assemblage — see Table of Numbers
2 : the property that a mathematical set has in common with all sets that can be put in one-to-one correspondence with it

Examples of cardinal number in a Sentence

Recent Examples on the Web The result means both axioms are more likely to be true, which in turn suggests that the number of real numbers is bigger than initially thought, corresponding to the cardinal number rather than the smaller (yet still infinite) . Quanta Magazine, 23 Dec. 2021 The cardinal number 𝔡 is defined as the smallest possible size of a set of continuous functions sufficient to dominate every possible continuous function. Martin Goldstern, Scientific American, 16 Aug. 2021 With the hypothesis unresolved, many other properties of cardinal numbers and infinity remain uncertain too. Quanta Magazine, 26 Nov. 2013

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cardinal number.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of cardinal number

1801, in the meaning defined at sense 1

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Time Traveler for cardinal number

Time Traveler

The first known use of cardinal number was in 1801

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Dictionary Entries Near cardinal number


cardinal number

cardinal point

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Cite this Entry

“Cardinal number.” Dictionary, Merriam-Webster, Accessed 13 Aug. 2022.

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More Definitions for cardinal number

cardinal number


Kids Definition of cardinal number

: a number (as 1, 5, 22) that is used in simple counting and answers the question "how many?"

More from Merriam-Webster on cardinal number

Nglish: Translation of cardinal number for Spanish Speakers Encyclopedia article about cardinal number


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