hieroglyphic vs magnum opus

hieroglyphic

noun
  • A writing system of ancient Egypt, Minoans, Maya and other civilizations, using pictorial symbols to represent individual sounds as a rebus 

  • Undecipherable handwriting or secret symbol. 

  • Any symbol used in this system; a hieroglyph. 

adj
  • difficult to decipher 

  • of, relating to, or written with this system of symbols 

magnum opus

noun
  • A great or important work of literature, music or art, a masterpiece. 

  • The best, most popular, or most renowned achievement of an author or artist, representing their major life effort. 

  • The process of working with the prima materia to create the philosopher's stone. 

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