goldeneye vs knapweed

goldeneye

noun
  • Any of several flowering plants of the subtribe Helianthinae. 

  • Any of several seaducks, of the genus Bucephala, having black and white plumage. 

  • Any of several lacewings of the family Chrysopidae. 

knapweed

noun
  • Any of various common weeds of the genus Centaurea 

  • especially Centaurea nigra. 

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