sponge 
(spŭnj)
(spŭnj)n.
1.
a. 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. Also called poriferan.
b. 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.
2. Metal in a porous, brittle form, as after the removal of other metals in processing, used as a raw material in manufacturing.
3. A gauze pad used to absorb blood and other fluids, as in surgery or the dressing of a wound.
4. A small absorbent contraceptive pad that contains a spermicide and is placed against the cervix of the uterus before sexual intercourse.
5. Dough that has been or is being leavened.
6. A light cake, such as sponge cake.
7. Informal One who habitually depends on others for one's own maintenance.
8. Slang A person who drinks large amounts of alcohol.
v. sponged, spong·ing, spong·es
v.tr.
1. To moisten, wipe, or clean with a sponge or cloth: sponge off the table.
2. To remove or absorb with a sponge or cloth: sponge off the sweat; sponge up the mess.
3. To apply or daub with a sponge: sponge paint on the wall.
4. Informal To obtain free, as by begging or freeloading: sponge a meal.
v.intr.
1. To harvest sponges.
2. Informal To obtain something such as food or money by relying on the generosity of others: sponged off her parents.
[Middle English, from Old English, from Latin spongia, from Greek spongiā, from spongos.]
spongetop: giant barrel sponge
Xestospongia muta
bottom: purple tube sponge
Aplysina lacunosa
sponge