keychain vs periapt

keychain

noun
  • An ornamental piece holding such a chain or ring. 

  • A chain or ring to which a key may be attached. 

  • A digital repository for the storage of cryptographic keys. 

periapt

noun
  • A charm worn on a necklace; an amulet. 

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