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ordinal number

American  

noun

  1. Also called ordinal numeral.  any of the numbers that express degree, quality, or position in a series, as first, second, and third (cardinal number ).

  2. Mathematics. a symbol denoting both the cardinal number and the ordering of a given set, being identical for two ordered sets having elements that can be placed into one-to-one correspondence, the correspondence preserving the order of the elements.


ordinal number British  

noun

  1. Sometimes shortened to: ordinal.  a number denoting relative position in a sequence, such as first, second, third

  2. logic maths a measure of not only the size of a set but also the order of its elements

"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

ordinal number Scientific  
/ ôrdn-əl /
  1. A number, such as 3rd, 11th, or 412th, used in counting to indicate position in a series but not quantity.

  2. Compare cardinal number


Etymology

Origin of ordinal number

First recorded in 1600–10

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The assumption is that something of the essence of institutions, public or private, small or large, religious or not, can be distilled by crunching data and assembling lists with ordinal numbers.

From Washington Post

Crunching ordinal numbers derived from other numbers is a tricky proposition and certainly statistically dubious.

From Washington Post

But they also define a school’s place in higher education through a single ordinal number derived from a subjective formula.

From Washington Post

News produces, and the ratings that Obama wants — without imposing any ordinal numbers on particular schools.

From Washington Post

In a new study in this month's Cognition, scientists show that Alex correctly inferred the relationship between cardinal and ordinal numbers, an ability that has not previously been found in any species other than humans.

From Science Magazine