From The Collaborative International Dictionary of English v.0.48:
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 (Xanlhorrh[oe]a).
Gum animal (Zool.), 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 juniper. See Sandarac.
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[aum]) 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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