craggy vs gradual

craggy

adj
  • Characterized by rugged, sharp, or coarse features. 

gradual

noun
  • A service book containing the musical portions of the Mass. 

  • An antiphon or responsory after the epistle, in the Mass, which was sung on the steps, or while the deacon ascended the steps. 

adj
  • Proceeding or advancing by small, slow, regular steps or degrees 

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