mediocrity vs nonesuch

mediocrity

noun
  • The condition of being mediocre; having only an average degree of quality, skills etc.; no better than standard. 

  • An individual with mediocre abilities or achievements. 

nonesuch

noun
  • Silene chalcedonica (syn. Lychnis chalcedonica) 

  • A person or thing with no equal. 

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