demilune vs half-moon

demilune

noun
  • A crescentic mass of granular protoplasm present in the salivary glands. 

  • A fortification constructed beyond the main ditch of a fortress, and in front of the curtain between two bastions, intended to defend the curtain; a ravelin. 

adj
  • In the shape of a half-moon, i.e. semicircular. 

half-moon

noun
  • Anything shaped like a crescent, especially the base of a fingernail. 

  • A semicircular or crescent-shaped Filipino butter cookie. 

  • The moon in its first or last quarter when only half the visible face is illuminated; a quarter moon. 

  • Synonym of black and white (“type of cookie”) 

How often have the words demilune and half-moon occurred in a corpus of books? (source: Google Ngram Viewer )