cochlea vs shellfish

cochlea

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

  • 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. 

shellfish

noun
  • A fisheries and colloquial term for an aquatic invertebrate having an inner or outer shell, such as a mollusc or crustacean, especially when edible. 

  • A culinary and nutritional term for several groups of non-piscine, non-tetrapod, aquatic animals that are used as a food source. The term often exclusively refers to edible aquatic crustaceans, bivalve mollusks and cephalopod mollusks; but sometimes echinoderms may be included as well. 

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