blemish vs graffiti

blemish

verb
  • To spoil the appearance of. 

  • To tarnish (reputation, character, etc.); to defame. 

noun
  • A moral defect; a character flaw. 

  • A small flaw which spoils the appearance of something, a stain, a spot. 

graffiti

verb
  • To mark a surface with such images. 

noun
  • Drawings or words drawn on a surface in a public place, usually made without authorization. 

  • Informal inscriptions, figure drawings, etc., as opposed to official inscriptions. 

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