gazehound vs sighthound

gazehound

noun
  • Synonym of sighthound (“a hound that primarily hunts by sight and speed, instead of by scent and endurance”) 

sighthound

noun
  • A hound that primarily hunts by sight and speed, instead of by scent and endurance. 

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