Source : Webster's Revised Unabridged Dictionary (1913)

Gum \Gum\, n. [OE. gome, AS. gama palate; akin Co G. gaumen,
   OHG. goumo, guomo, Icel. g?mr, Sw. gom; cf. Gr. ? to gape.]
   The dense tissues which invest the teeth, and cover the
   adjacent parts of the jaws.

   {Gum rash} (Med.), strophulus in a teething child; red gum.
      

   {Gum stick}, a smooth hard substance for children to bite
      upon while teething.

Gum \Gum\, v. t. [imp. &. p. {Gummed}; p. pr. & vb. n.
   {Gumming}.]
   To smear with gum; to close with gum; to unite or stiffen by
   gum or a gumlike substance; to make sticky with a gumlike
   substance.

         He frets likke a gummed velvet.Shak.

Gum \Gum\, v. i.
   To exude or from gum; to become gummy.

Gum \Gum\, v. t.
   To deepen and enlarge the spaces between the teeth of (a worn
   saw). See {Gummer}.

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.

   2. (Bot.) See {Gum tree}, {below}.

   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.]

   4. A rubber overshoe. [Local, U. S.]

   {Black gum}, {Blue gum}, {British gum}, etc. See under
      {Black}, {Blue}, etc.

   {Gum Acaroidea}, the resinous gum of the Australian grass
      tree ({Xanlhorrh[oe]a}).

   {Gum animal} (Zo["o]l.), the galago of West Africa; -- so
      called because it feeds on gums. See {Galago}.

   {Gum animi or anim['e]}. See {Anim['e]}.

   {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 ({Amygdalace[ae]},
      {Cactace[ae]}, 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. Adansoni["a]}) growing in the
      Senegal country, West Africa.

   {Gum tragacanth}. See {Tragacanth}.

   {Gum tree}, the name given to several trees in America and
      Australia:
      (a) The black gum ({Nyssa multiflora}), one of the largest
          trees of the Southern States, bearing a small blue
          fruit, the favorite food of the opossum. Most of the
          large trees become hollow.
      (b) A tree of the genus {Eucalyptus.} See {Eucalpytus.}
      (c) The sweet gum tree of the United States ({Liquidambar
          styraciflua}), a large and beautiful tree with
          pointedly lobed leaves and woody burlike fruit. It
          exudes an aromatic terebinthine juice.

   {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.

Source : WordNet®

gum
     n 1: a preparation (usually made of sweetened chicle) for chewing
          [syn: {chewing gum}]
     2: the tissue (covered by mucous membrane) of the jaws that
        surrounds the bases of the teeth [syn: {gingiva}]
     3: any of various substances (soluble in water) that exude from
        certain plants; they are gelatinous when moist but harden
        on drying
     4: cement consisting of a sticky substance that is used as an
        adhesive [syn: {glue}, {mucilage}]
     5: wood or lumber from any of various gum trees especially the
        sweet gum [syn: {gumwood}]
     6: any of various trees of the genera Eucalyptus or Liquidambar
        or Nyssa that are sources of gum [syn: {gum tree}]
     [also: {gumming}, {gummed}]

gum
     v 1: grind with the gums; chew without teeth and with great
          difficulty; "the old man had no teeth left and mumbled
          his food" [syn: {mumble}]
     2: exude or form gum; "these trees gum in the Spring"
     [also: {gumming}, {gummed}]