cardinality

American  

[kahr-dn-al-i-tee] / ˌkɑr dnˈæl ɪ ti /

noun

Mathematics.

plural

cardinalities

1. (of a set) the cardinal number indicating the number of elements in the set.

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cardinality British  

/ ˌkɑːdɪˈnælɪtɪ /

noun

1. maths the property of possessing a cardinal number

2. maths logic (of a class) the cardinal number associated with the given class. Two classes have the same cardinality if they can be put in one-to-one correspondence

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Etymology

Origin of cardinality

First recorded in 1930–35; cardinal + -ity

Example Sentences

The sets presented so far all have the same cardinality.

From Scientific American • Jul. 13, 2023

But if you can assign exactly one seat to each person, then both sets are exactly the same size and thus have the same cardinality.

From Scientific American • Jul. 13, 2023

As Cantor was able to show, the cardinality of the natural numbers is the smallest possible infinity.

From Scientific American • May 23, 2023

The converse is not true: a subset of the x-y plane with a large cardinality need be neither measurable nor of large measure.

From Scientific American • Aug. 16, 2021

People of those times thought in terms of the old-style equivalence of cardinality and ordinality.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife