Definition of boat sponge in English:

boat sponge

noun

  • 1A sea sponge native to the Mediterranean, Hippospongia communis (family Spongidae), widely harvested and prepared to produce a high quality, soft household and cosmetic sponge; also called honeycomb sponge.

  • 2A natural or artificial sponge used to clean or bail water out of a boat.

Origin

Mid 19th century; earliest use found in United States Economist.