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 With the hypothesis unresolved, many other properties of cardinal numbers and infinity remain uncertain too. Quanta Magazine, "To Settle Infinity Dispute, a New Law of Logic," 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

1591, in the meaning defined at sense 1

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The first known use of cardinal number was in 1591

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Cite this Entry

“Cardinal number.” Dictionary, Merriam-Webster, Accessed 11 May. 2021.

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More Definitions for cardinal number

cardinal number


English Language Learners Definition of cardinal number

: a number (such as 1, 2, or 3) that is used in simple counting and shows quantity

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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