(n) deciduous tree of the Amazon and Orinoco Rivers having leathery leaves and fragrant yellow-white flowers; it yields a milky juice that is the chief source of commercial rubber, Syn. Hevea brasiliensis, caoutchouc tree
. The caoutchouc obtained from the South American euphorbiaceous tree Hevea brasiliensis, hence called the Pará rubber tree, from the Brazilian river and seaport named Pará; also, the similar product of other species of Hevea. It is usually exported in flat round cakes, and is a chief variety of commercial India rubber. [ Webster 1913 Suppl. ]