"Three" is a cardinal number, while "third" is an ordinal number.
A number used to denote quantity; a counting number.
The smallest cardinal numbers are 0, 1, 2, and 3.
The cardinal number "three" can be represented as "3" or "three".
(mathematics) A generalized kind of number used to denote the size of a set, including infinite sets.
Attributive form of cardinal number, noun.
A number, such as 3, 11, or 412, used in counting to indicate quantity but not order.
Other Word Forms
Cardinal-number Sentence Examples
Two classes between which a one-one relation exists have the same cardinal number and are called cardinally similar; and the cardinal number of the class a is a certain class whose members are themselves classes - namely, it is the class composed of all those classes for which a one-one correlation with a exists.
Thus the cardinal number of a is itself a class, and furthermore a is a member of it.
Thus the cardinal number one is the class of unit classes, the cardinal number two is the class of doublets, and so on.
The cardinal number zero is the class of classes with no members; but there is only one such class, namely - the null class.