ordinal

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ordinal

(ôr′dn-əl)
adj.
1. Being of a specified position in a numbered series: an ordinal rank of seventh.
2. Of or relating to a taxonomic order.
n.
An ordinal number.
References in periodicals archive ?
The difference between cardinal and ordinal numbers is simple to understand, but the significance of this distinction does not become obvious until infinite sets are considered.
At the finite level every set can be well ordered, also this ordering is unique: you cannot change the ordinal value of a finite set by rearranging its elements.
Every ordinal number is a transitive set, well ordered by the relation of belonging.
After the rather benign and simple relation between cardinal and ordinal numbers at the finite level, their divergence at the infinite level is quite fascinating.
o]), the set of all possible subsets of countable, natural, numbers is exhausted by the ordered methods of construction deployed by ordinal generation: p([[?
This idea recalls the common philosophical theme of duality; a set has its intrinsic ordinal structure, and its purely extrinsic cardinal magnitude: an intensive form and an extensive content.
Here the relation between a set's extensional, cardinal, existence and its intentional, ordinal, construction share an absolute minimal relation: everything that exists is constructible according to the rules of ordinal generation.