\Caout"chouc\, n. [F. caoutchouc, from the South
American name.]
A tenacious, elastic, gummy substance obtained from the milky
sap of several plants of tropical South America (esp. the
euphorbiaceous tree {Siphonia elastica} or {Hevea
caoutchouc}), Asia, and Africa. Being impermeable to liquids
and gases, and not readly affected by exposure to air, acids,
and alkalies, it is used, especially when vulcanized, for
many purposes in the arts and in manufactures. Also called
{India rubber} (because it was first brought from India, and
was formerly used chiefly for erasing pencil marks) and {gum
elastic}. See {Vulcanization}.
{Mineral caoutchouc}. See under {Mineral}.