incision vs snipping

incision

noun
  • The act of cutting into a substance. 

  • A cut-back 

  • A cut, especially one made by a scalpel or similar medical tool in the context of surgical operation; the scar resulting from such a cut. 

snipping

noun
  • The act by which something is snipped or cut. 

  • A piece cut off; a clipping. 

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