Source : Webster's Revised Unabridged Dictionary (1913)

Sponge \Sponge\, n. [OF. esponge, F. ['e]ponge, L. spongia, Gr.
   ?, ?. Cf. {Fungus}, {Spunk}.] [Formerly written also
   {spunge}.]
   1. (Zo["o]l.) Any one of numerous species of Spongi[ae], or
      Porifera. See Illust. and Note under {Spongi[ae]}.

   2. The elastic fibrous skeleton of many species of horny
      Spongi[ae] (keratosa), used for many purposes, especially
      the varieties of the genus {Spongia}. The most valuable
      sponges are found in the Mediterranean and the Red Sea,
      and on the coasts of Florida and the West Indies.

   3. Fig.: One who lives upon others; a pertinaceous and
      indolent dependent; a parasite; a sponger.

   4. Any spongelike substance. Specifically:
      (a) Dough before it is kneaded and formed into loaves, and
          after it is converted into a light, spongy mass by the
          agency of the yeast or leaven.
      (b) Iron from the puddling furnace, in a pasty condition.
      (c) Iron ore, in masses, reduced but not melted or worked.

   5. (Gun.) A mop for cleaning the bore of a cannon after a
      discharge. It consists of a cylinder of wood, covered with
      sheepskin with the wool on, or cloth with a heavy looped
      nap, and having a handle, or staff.

   6. (Far.) The extremity, or point, of a horseshoe, answering
      to the heel.

   {Bath sponge}, any one of several varieties of coarse
      commercial sponges, especially {Spongia equina}.

   {Cup sponge}, a toilet sponge growing in a cup-shaped form.
      

   {Glass sponge}. See {Glass-sponge}, in the Vocabulary.

   {Glove sponge}, a variety of commercial sponge ({Spongia
      officinalis}, variety {tubulufera}), having very fine
      fibers, native of Florida, and the West Indies.

   {Grass sponge}, any one of several varieties of coarse
      commercial sponges having the surface irregularly tufted,
      as {Spongia graminea}, and {S. equina}, variety
      {cerebriformis}, of Florida and the West Indies.

   {Horse sponge}, a coarse commercial sponge, especially
      {Spongia equina}.

   {Platinum sponge}. (Chem.) See under {Platinum}.

   {Pyrotechnical sponge}, a substance made of mushrooms or
      fungi, which are boiled in water, dried, and beaten, then
      put in a strong lye prepared with saltpeter, and again
      dried in an oven. This makes the black match, or tinder,
      brought from Germany.

   {Sheep's-wool sponge}, a fine and durable commercial sponge
      ({Spongia equina}, variety {gossypina}) found in Florida
      and the West Indies. The surface is covered with larger
      and smaller tufts, having the oscula between them.

   {Sponge cake}, a kind of sweet cake which is light and
      spongy.

   {Sponge lead}, or {Spongy lead} (Chem.), metallic lead
      brought to a spongy form by reduction of lead salts, or by
      compressing finely divided lead; -- used in secondary
      batteries and otherwise.

   {Sponge tree} (Bot.), a tropical leguminous tree ({Acacia
      Farnesiana}), with deliciously fragrant flowers, which are
      used in perfumery.

   {Toilet sponge}, a very fine and superior variety of
      Mediterranean sponge ({Spongia officinalis}, variety
      {Mediterranea}); -- called also {turkish sponge}.

   {To set a sponge} (Cookery), to leaven a small mass of flour,
      to be used in leavening a larger quantity.

   {To throw up the sponge}, to give up a contest; to
      acknowledge defeat; -- from a custom of the prize ring,
      the person employed to sponge a pugilist between rounds
      throwing his sponge in the air in token of defeat. [Cant
      or Slang] ``He was too brave a man to throw up the sponge
      to fate.'' --Lowell.