keychain vs wampum

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. 

wampum

noun
  • A string of such beads. 

  • Small beads made from polished shells, especially white ones, formerly used as money and jewelry by certain Native American peoples. 

  • Money. 

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