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cardinal number

noun
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. 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.
Origin
1585-1595
1585-95
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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British Dictionary definitions for cardinal numeral

cardinal number

noun
1.
a number denoting quantity but not order in a set Sometimes shortened to cardinal
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
Compare ordinal number
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for cardinal numeral

cardinal number

n.

1590s, "one, two, three," etc. as opposed to ordinal numbers "first, second, third," etc.; so called because they are the principal numbers and the ordinals depend on them (see cardinal (adj.)).

Online Etymology Dictionary, © 2010 Douglas Harper
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cardinal numeral in Science
cardinal number
  (kär'dn-əl)   
A number, such as 3, 11, or 412, used in counting to indicate quantity but not order. Compare ordinal number.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Word Value for cardinal

11
14
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