blur vs dirt

blur

verb
  • To smear, stain or smudge. 

  • To cause imperfection of vision in; to dim; to darken. 

  • To become indistinct. 

  • To transfer the input focus away from. 

  • To make indistinct or hazy, to obscure or dim. 

adj
  • In a state of doubt or confusion. 

noun
  • Something that appears hazy or indistinct 

  • A smear, smudge or blot 

dirt

verb
  • To make foul or filthy; soil; befoul; dirty 

noun
  • A stain or spot (on clothes etc); any foreign substance that worsens appearance. 

  • Previously unknown facts, or the invented "facts", about a person. 

  • Meanness; sordidness. 

  • In placer mining, earth, gravel, etc., before washing. 

  • freckles 

  • Soil or earth. 

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