cleft vs ravine

cleft

adj
  • split, divided, or partially divided into two. 

noun
  • An opening, fissure, or V-shaped indentation made by or as if by splitting. 

  • A piece made by splitting. 

  • A disease of horses; a crack on the band of the pastern. 

verb
  • To syntactically separate a prominent constituent from the rest of the clause that concerns it, such as threat in "The threat which I saw but which he didn't see, was his downfall." 

ravine

noun
  • A deep narrow valley or gorge in the earth's surface worn by running water. 

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