placard vs suit of armor

placard

noun
  • An extra plate on the lower part of the breastplate or backplate of armour. 

  • A kind of stomacher, often adorned with jewels, worn in the fifteenth century and later. 

  • The woodwork and frame of the door of a closet etc. 

  • A sheet of paper or cardboard with a written or printed announcement on one side for display in a public place. 

verb
  • To announce with placards. 

  • To affix a placard to. 

suit of armor

noun
  • A collection of garments, usually made of metal, worn over the body for protection in battle from weapons. 

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