hazel vs horse chestnut

hazel

noun
  • The nut of the hazel tree. 

  • The wood of a hazelnut tree. 

  • Freestone. 

  • A tree or shrub of the genus Corylus, bearing edible nuts called hazelnuts or filberts. 

  • A greenish-brown colour, the colour of a ripe hazelnut. 

adj
  • Of a greenish-brown colour. (often used to refer to eye colour) 

horse chestnut

noun
  • The large nutlike seed of these trees. 

  • Any of several tree species of genus Aesculus, especially Aesculus hippocastanum, common in temperate northern hemisphere. 

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