prone vs slanty

prone

adj
  • Having a downward inclination or slope. 

  • Of the hand, forearm or foot: turned facing away from the body; with the thumb inward or big toe downward. 

  • Lying face downward. 

  • Predisposed, liable, inclined. 

verb
  • To place in a prone position, to place face down. 

slanty

adj
  • slanted 

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