caryopsis vs coccus

caryopsis

noun
  • A type of fruit in which the fruit skin is stuck to the seed coat; especially the grain of a cereal. 

coccus

noun
  • One of the carpels or seed-vessels of a dry fruit. 

  • Any approximately spherical bacterium. 

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