blue bonnet vs blueberry

blue bonnet

noun
  • A traditional flat Scottish hat made of blue wool; a blue tam-o'-shanter. 

  • A blue Australian parrot, especially Northiella haematogaster. 

  • Any of several blue flowering plants, especially cornflower, Centaurea cyanus, and plants of the genus Scabiosa. 

  • Someone who wears such a hat; a Scotsman, especially a Scottish soldier. 

  • Any of several North American species of Lupinus common in the southwestern US, especially Lupinus texensis and Lupinus subcarnosus. 

blueberry

noun
  • A dark blue colour. 

  • The shrub of the above-mentioned berry. 

  • An edible round berry, belonging to the cowberry group (Vaccinium sect. Cyanococcus), with flared crowns at the end, that turns blue on ripening. 

adj
  • Of a dark blue colour. 

verb
  • To gather or forage for blueberries. 

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