engraving vs monoprint

engraving

noun
  • The art of producing an image from an engraved printing form, typically made of copper. 

  • A print produced from an engraving. 

  • The art of drawing music notation at high quality, particularly on a computer. 

  • The practice of incising a design onto a hard, flat surface, by cutting grooves into it. 

monoprint

noun
  • A form of printing on paper from a glass sheet to which oil paint has been applied; monotype. 

verb
  • To print using this technique. 

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