resin

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Any of numerous clear to translucent yellow or brown, solid or semisolid, viscous substances of plant origin, such as copal, rosin, and amber, used principally in lacquers, varnishes, inks, adhesives, synthetic plastics, and pharmaceuticals.
2. n. Any of numerous physically similar polymerized synthetics or chemically modified natural resins including thermoplastic materials such as polyvinyl, polystyrene, and polyethylene and thermosetting materials such as polyesters, epoxies, and silicones that are used with fillers, stabilizers, pigments, and other components to form plastics.
3. v. To treat or rub with resin.

Century Dictionary and Cyclopedia

1. n. A hardened secretion found in many species of plants, or a substance produced by exposure of the secretion to the air. It is allied to and probably derived from a volatile oil. The typical resins are oxidized hydrocarbons, amorphous, brittle, having a vitreous fracture, insoluble in water, and freely soluble in alcohol, ether, and volatile oils. They unite with alkalis to form soaps. They melt at a low heat, are non-volatile, and burn quickly with a smoky flame. The hardest resins are fossilized like amber and copal, but they show all gradations of hardness through oleoresins and balsams to essential oils. The hard resins are nearly inodorous, and contain little or no volatile oil; the soft resins owe their softness to the volatile oil associated with them. The common resin of commerce exudes in a semi-fluid state from several species of pine (in the United States, chiefly the long-leaved pine). From this the oil of turpentine is separated by distillation. Resins are largely used in the preparation of varnishes, and several are used in medicine. See gum.
2. n. The precipitate formed by treating a tincture with water.
3. n. See rosin, 2.
4. To treat, rub, or coat with resin.

Wiktionary

1. n. A viscous hydrocarbon secretion of many plants, particularly coniferous trees.
2. n. Any of various yellowish viscous liquids or soft solids of plant origin; used in lacquers, varnishes and many other applications; chemically they are mostly hydrocarbons, often polycyclic.
3. n. Any synthetic compound of similar properties.

GNU Webster's 1913

1. n. Any one of a class of yellowish brown solid inflammable substances, of vegetable origin, which are nonconductors of electricity, have a vitreous fracture, and are soluble in ether, alcohol, and essential oils, but not in water; specif., pine resin (see rosin).
2. n. Any of various polymeric substance resembling the natural resins[1], prepared synthetically; -- they are used, especially in particulate form, in research and industry for their property of specifically absorbing or adsorbing substances of particular types; they are especially useful in separation processes such as chromatography.

WordNet 3.0

1. n. any of a class of solid or semisolid viscous substances obtained either as exudations from certain plants or prepared by polymerization of simple molecules