nonuniversal vs unfrequent

nonuniversal

adj
  • Not universal. 

noun
  • That which is not universal. 

unfrequent

adj
  • Not frequent; not common; not happening often; infrequent. 

verb
  • To stop frequenting; cease to frequent. 

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