cochlea vs earplug

cochlea

noun
  • The complex, spirally coiled, tapered cavity of the inner ear of higher vertebrates, which contains the organ of Corti and in which sound vibrations are converted into nerve impulses. 

  • A spiral-shaped shell, especially that of a snail. 

earplug

noun
  • A piece of protective gear meant to be inserted in the ear canal to protect the wearer's hearing from loud noises or the intrusion of water. 

verb
  • To fit with earplugs. 

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