myriad vs variosity

myriad

noun
  • A countless number or multitude (of specified things) 

  • Ten thousand; 10,000 

adj
  • Great in number; innumerable, multitudinous 

  • Multifaceted, having innumerable elements 

variosity

noun
  • Synonym of variety 

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