Definition of cardinal number
1
: a number (such as 1, 5, 15) that is used in simple counting and that indicates how many elements there are in an assemblage — see Table of Numbers
2
: the property that a mathematical set has in common with all sets that can be put in one-to-one correspondence with it
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Merriam-Webster unabridged
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Time Traveler for cardinal number
The first known use of cardinal number was in 1801
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