many vs myriad

many

adj
  • Existing in large number; numerous. 

det
  • An indefinite large number of. 

  • Used to indicate, demonstrate or compare the number of people or things. 

noun
  • A considerable number. 

  • A multitude; a great aggregate; a mass of people; the generality; the common herd. 

pron
  • An indefinite large number of people or things. 

myriad

adj
  • Great in number; innumerable, multitudinous 

  • Multifaceted, having innumerable elements 

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

  • Ten thousand; 10,000 

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