car·​di·​nal·​i·​ty | \ ˌkär-də-ˈna-lə-tē How to pronounce cardinality (audio) \
plural cardinalities

Definition of cardinality

: the number of elements in a given mathematical set

Examples of cardinality in a Sentence

Recent Examples on the Web The set of real numbers has a bigger cardinality than the natural numbers because there are more of them. Quanta Magazine, 10 Aug. 2021 Cantor also proved that the infinite number of points on a line has the same cardinality as the infinite number of points that fill the volume of a shape, like a sphere. Quanta Magazine, 26 Aug. 2021 Alternatively, it could be termed something else: cardinality, for example. Martin Goldstern, Scientific American, 16 Aug. 2021 Who’s discussing ephemeral infinite cardinality then? Adrian Bridgwater, Forbes, 7 May 2021 In an ephemeral world of shifting clouds and infinite cardinality, the need to grasp some human sense of observability is key to our operational lifeblood. Adrian Bridgwater, Forbes, 7 May 2021

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

First Known Use of cardinality

1935, in the meaning defined above

History and Etymology for cardinality

cardinal entry 1 + -ity

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Time Traveler for cardinality

Time Traveler

The first known use of cardinality was in 1935

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Dictionary Entries Near cardinality



cardinal number

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Statistics for cardinality

Cite this Entry

“Cardinality.” Dictionary, Merriam-Webster, Accessed 8 Aug. 2022.

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More from Merriam-Webster on cardinality

Britannica English: Translation of cardinality for Arabic Speakers


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