hoof vs ungula

hoof

noun
  • The tip of a toe of an ungulate such as a horse, ox or deer, strengthened by a thick keratin covering. 

  • The human foot. 

verb
  • To trample with hooves. 

  • To dance, especially as a professional. 

  • To kick, especially to kick a football a long way downfield with little accuracy. 

  • To walk. 

ungula

noun
  • A hoof, claw, or talon. 

  • A section of a cylinder, cone, or other solid of revolution, cut off by a plane oblique to the base; so called from its resemblance to the hoof of a horse. [[File:Ungula (PSF).png|thumb|]] 

  • A surgical instrument for use in removing a dead fetus. 

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