centenarian vs fossil

centenarian

noun
  • One who or that which is at least 100 years old. 

adj
  • Aged 100 years or more; extremely old. 

  • Of or relating to centenarians or a centenary celebration. 

fossil

noun
  • An extremely old or outdated person. 

  • The mineralized remains of an animal or plant. 

  • Any preserved evidence of ancient life, including shells, imprints, burrows, coprolites, and organically-produced chemicals. 

  • Anything extremely old, extinct, or outdated. 

  • A fossil word. 

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