underline vs xylograph

underline

noun
  • A line placed underneath a piece of text in order to provide emphasis or to indicate that it should be viewed in italics or (in electronic documents) that it acts as a hyperlink. 

  • The character _. 

adj
  • Passing under a railway line. 

verb
  • To emphasise or stress something 

  • To draw a line underneath something, especially to add emphasis; to underscore 

xylograph

noun
  • A print taken from such an engraving. 

  • An engraving in wood or woodcut, especially one used in printing predating the Western tradition (14th c.). 

verb
  • To make a print from an engraving in wood. 

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