sponge

Any of numerous aquatic, chiefly marine filter-feeding invertebrate animals of the phylum Porifera, characteristically having a porous skeleton composed of fibrous material or siliceous or calcareous spicules and often forming colonies attached to an underwater surface.

A piece of the absorbent skeleton of certain of these organisms, or a piece of plastic or another material that is similar in absorbency, used for cleaning, bathing, and other purposes.

Metal in a porous, brittle form, as after the removal of other metals in processing, used as a raw material in manufacturing.

A gauze pad used to absorb blood and other fluids, as in surgery or the dressing of a wound.

A small absorbent contraceptive pad that contains a spermicide and is placed against the cervix of the uterus before sexual intercourse.