Gum \Gum\, n. [OE. gomme, gumme, F. gomme, L. gummi and commis,
   fr. Gr. ?, prob. from an Egyptian form kam?; cf. It.
   {gomma}.]
   1. A vegetable secretion of many trees or plants that hardens
      when it exudes, but is soluble in water; as, gum arabic;
      gum tragacanth; the gum of the cherry tree. Also, with
      less propriety, exudations that are not soluble in water;
      as, gum copal and gum sandarac, which are really resins.
      
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   2. (Bot.) See {Gum tree}, {below}.
      
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   3. A hive made of a section of a hollow gum tree; hence, any
      roughly made hive; also, a vessel or bin made of a hollow
      log. [Southern U. S.]
      
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   4. A rubber overshoe. [Local, U. S.]
      
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   {Black gum}, {Blue gum}, {British gum}, etc. See under
      {Black}, {Blue}, etc.

   {Gum Acaroidea}, the resinous gum of the Australian grass
      tree ({Xanlhorrhoea}).

   {Gum animal} (Zool.), the galago of West Africa; -- so called
      because it feeds on gums. See {Galago}.

   {Gum animi or anime}. See {Anime}.

   {Gum arabic}, a gum yielded mostly by several species of
      {Acacia} (chiefly {A. vera} and {A. Arabica}) growing in
      Africa and Southern Asia; -- called also {gum acacia}.
      East Indian gum arabic comes from a tree of the Orange
      family which bears the elephant apple.

   {Gum butea}, a gum yielded by the Indian plants {Butea  frondosa} and {B. superba}, and used locally in tanning
      and in precipitating indigo.

   {Gum cistus}, a plant of the genus {Cistus} ({Cistus  ladaniferus}), a species of rock rose.

   {Gum dragon}. See {Tragacanth}.

   {Gum elastic}, {Elastic gum}. See {Caoutchouc}.

   {Gum elemi}. See {Elemi}.

   {Gum juniper}. See {Sandarac}.

   {Gum kino}. See under {Kino}.

   {Gum lac}. See {Lac}.

   {Gum Ladanum}, a fragrant gum yielded by several Oriental
      species of Cistus or rock rose.

   {Gum passages}, sap receptacles extending through the
      parenchyma of certain plants ({Amygdalaceae},
      {Cactaceae}, etc.), and affording passage for gum.

   {Gum pot}, a varnish maker's utensil for melting gum and
      mixing other ingredients.

   {Gum resin}, the milky juice of a plant solidified by
      exposure to air; one of certain inspissated saps, mixtures
      of, or having properties of, gum and resin; a resin
      containing more or less mucilaginous and gummy matter.

   {Gum sandarac}. See {Sandarac}.

   {Gum Senegal}, a gum similar to gum arabic, yielded by trees
      ({Acacia Verek} and {A. Adansoniaum}) growing in the
      Senegal country, West Africa.

   {Gum tragacanth}. See {Tragacanth}.

   {Gum water}, a solution of gum, esp. of gum arabic, in water.
      

   {Gum wood}, the wood of any gum tree, esp. the wood of the
      {Eucalyptus piperita}, of New South Wales.
      
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