cleavage vs scarification

cleavage

noun
  • The act of cleaving or the state of being cleft. 

  • The repeated division of a cell into daughter cells after mitosis. 

  • The hollow or separation between a woman's breasts, especially as revealed by a low neckline. 

  • The tendency of a crystal to split along specific planes. 

  • Any similar separation between two body parts, such as the buttocks or toes. 

  • The splitting of a large molecule into smaller ones. 

  • The division of voters into voting blocs. 

scarification

noun
  • The act of scarifying: raking the ground harshly to remove weeds, etc. 

  • A medieval form of penance in which the skin was damaged with a knife or hot iron. 

  • A route of administration for some vaccinations and tests: rather than hypodermic injection, the site is inoculated intradermally not with any injection but rather only with small, shallow pricks or scratches; the needle is not hollow. 

  • The scratching, etching, burning / branding, or superficially cutting designs, pictures, or words into the skin as a permanent body modification. 

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