cardinal number vs ordinal number

cardinal number

noun
  • A generalized kind of number used to denote the size of a set, including infinite sets. 

  • A word that expresses a countable quantity; a cardinal numeral. 

  • A number used to denote quantity; a counting number; a cardinal. 

ordinal number

noun
  • Such a number generalised to correspond to any cardinal number (the size of some set); formally, the order type of some well-ordered set of some cardinality a, which represents an equivalence class of well-ordered sets (exactly those of cardinality a) under the equivalence relation "existence of an order-preserving bijection". 

  • A natural number used to denote position in a sequence. 

  • A word that expresses the relative position of an item in a sequence. 

How often have the words cardinal number and ordinal number occurred in a corpus of books? (source: Google Ngram Viewer )