cardinal number

American  

[kahr-dn-l nuhm-ber] / ˈkɑr dn l ˈnʌm bər /

noun

1. Also called cardinal numeral.  any of the numbers that express amount, as one, two, three, etc. (distinguished from ordinal number).

2. Also called potency, power.  Mathematics. a number or symbol analogous to the number of elements in a finite set, being identical for two sets that can be placed into one-to-one correspondence.

   The cardinal number of the set a1, a2, … an is n.

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cardinal number British  

noun

1. Sometimes shortened to: cardinal.  a number denoting quantity but not order in a set

2. maths logic

   1. a measure of the size of a set that does not take account of the order of its members Compare natural number

   2. a particular number having this function

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cardinal number Scientific  

/ kär′dn-əl /

1. A number, such as 3, 11, or 412, used in counting to indicate quantity but not order.

2. Compare ordinal number

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Etymology

Origin of cardinal number

First recorded in 1585–95

Example Sentences

For every infinite cardinal ℵa, there is a next larger cardinal number ℵa+1.

From Scientific American • Aug. 16, 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.

From Scientific American • Aug. 16, 2021

I suspect that Macrobius, in his representation, has mistaken the cardinal number for the ordinal; and that what he renders one should be first, or chief.

From A New System; or, an Analysis of Antient Mythology. Volume I. by Bryant, Jacob

Two equally numerous collections appear to have something in common: this something is supposed to be their cardinal number.

From Mysticism and Logic and Other Essays by Russell, Bertrand

The notion of order, which is here introduced, is one which is not required in the theory of cardinal number.

From Our Knowledge of the External World as a Field for Scientific Method in Philosophy by Russell, Bertrand