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 . Math. 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 a 1 , a 2 , ... a n is n.
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