legality vs validity

legality

noun
  • Lawfulness. 

  • A dice game; the same as chuck-a-luck. 

validity

noun
  • State of having legal force. 

  • The genuinity - as distinguished from the efficacity or the regularity - of a sacrament as a result of some formal dispositions being fulfilled. 

  • The state of being valid, authentic or genuine. 

  • A quality of a measurement indicating the degree to which the measure reflects the underlying construct, that is, whether it measures what it purports to measure (see reliability). 

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