bath sponge vs parazoan

bath sponge

noun
  • A commercially used species of sponge (porifer, invertebrate of the phylum Porifera) found throughout the Mediterranean Sea, Spongia officinalis. 

  • A sponge, made from any material, that is used for cleaning the body while bathing. 

parazoan

noun
  • Any sponge (of the subkingdom Parazoa) 

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