breastplate vs helmet

breastplate

noun
  • A piece of armor that covers the chest. 

  • A piece of horse tack designed to prevent the saddle slipping backwards. 

  • A piece of silicone in the shape of women's breasts worn by drag queens and other female impersonators to simulate a female body shape. 

  • An embroidered square of linen worn on the breast of the Jewish high priest, bearing twelve precious stones, each inscribed with the name of one of the tribes of Israel. 

helmet

noun
  • A hard, protective head covering, typically part of armour. 

  • The hood-shaped upper sepal or petal of some flowers, as of the monkshood or the snapdragon. 

  • A naked shield or protuberance on the top or fore part of the head of a bird. 

  • The feature above a shield on a coat of arms. 

  • The glans penis. 

  • A contemptible or stupid person. 

  • The upper part of a chemist's retort. 

verb
  • To cover with, or as if with, a helmet. 

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