coward vs mollusc

coward

noun
  • A person who lacks courage. 

adj
  • Cowardly. 

  • Borne in the escutcheon with his tail doubled between his legs. 

mollusc

noun
  • A weak-willed person. 

  • A soft-bodied invertebrate of the phylum Mollusca, typically with a hard shell of one or more pieces. 

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