aptitude vs cardinality

aptitude

noun
  • The condition of being suitable. 

  • Natural ability to acquire knowledge or skill. 

cardinality

noun
  • The status of being cardinalitial 

  • The number of terms that can inhabit a type; the possible values of a type. 

  • The number of elements a given set contains. 

  • The property of a relationship between a database table and another one, specifying whether it is one-to-one, one-to-many, many-to-one, or many-to-many. 

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