gutta-percha

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A rubbery substance derived from the latex of any of several tropical trees chiefly of the genus Palaquium of Southeast Asia, used in dental devices and formerly as an electrical insulator and in golf balls.

from The Century Dictionary.

• noun In geology, an exceedingly fine, laminated glacial clay.
• noun The concrete juice of an evergreen sapotaceous tree, Dichopsis (Isonandra) Gutta, common in the jungles of the Malay peninsula and archipelago.

from the GNU version of the Collaborative International Dictionary of English.

• noun A concrete juice produced by various trees found in the Malayan archipelago, especially by the Isonandra Gutta, syn. Dichopsis Gutta. It becomes soft, and unpressible at the tamperature of boiling water, and, on cooling, retains its new shape. It dissolves in oils and ethers, but not in water. In many of its properties it resembles caoutchouc, and it is extensively used for many economical purposes. The Mimusops globosa of Guiana also yields this material.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An inelastic natural latex, produced from the sap of several tropical trees of the genera Palaquium and Payena.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a whitish rubber derived from the coagulated milky latex of gutta-percha trees; used for insulation of electrical cables