bravura vs hairline

bravura

noun
  • A highly technical or difficult piece, usually written for effect. 

  • A display of daring. 

adj
  • Overly showy; ostentatious. 

hairline

noun
  • A very thin line in writing, drawing, or typography. 

  • A fishing line made from hair. 

  • The line along one's forehead where hair starts growing. 

  • A very thin fissure. 

adj
  • very thin, as thin as a hair 

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