The term 'sponge type' can be broken down into two crossword solutions: SEA (3 letters). The term 'SEA' is used to describe the large body of salt water that covers most of the Earth's surface. It is also used to refer to any large area of water, such as an ocean or a lake. In this context, 'sponge type' could refer to a type of SEA sponge, which is a type of aquatic animal that lives in the ocean and is composed of a porous skeleton made of calcium carbonate.