cardinal number

noun3

1. •
   A number used to denote quantity; a counting number; a cardinal.

   • The smallest cardinal numbers are 0, 1, 2, and 3.
   • The cardinal number “three” can be represented as “3” or “three”.
2. •
   A generalized kind of number used to denote the size of a set, including infinite sets.
3. •
   A word that expresses a countable quantity; a cardinal numeral.

   • “Three” is a cardinal number, while “third” is an ordinal number.