cardinal number vs cardinal numeral

cardinal number

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

  • 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. 

cardinal numeral

noun
  • A word used to represent a cardinal number. 

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