bath sponge vs sponger

bath sponge

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

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

sponger

noun
  • One who uses a sponge. 

  • A device for sponging cloth by means of a perforated adjustable cylinder. 

  • A parasitic hanger-on. 

  • A person or vessel employed in gathering sponges from the sea. 

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