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.

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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

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ordinal number Scientific  

/ ôr′dn-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

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Etymology

Origin of ordinal number

First recorded in 1600–10