# cardinal number

[ kahr-dn-l nuhm-ber ]

## noun

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

cardinal number

## noun

1. a number denoting quantity but not order in a set Sometimes shortened tocardinal
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

cardinal number

/ kärdn-əl /

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

## Word History and Origins

Origin of cardinal number1

First recorded in 1585–95

## Example Sentences

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

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

What business has this cardinal number octiesque uno in a row of ordinals?

The Latin language often employed the ordinal number instead of the cardinal number.

Thus the cardinal number one is the class of unit classes, the cardinal number two is the class of doublets, and so on.