Resin \Res"in\ (r?z"?n), n. [F. r['e]sine, L. resina; cf. Gr. "rhti`nh Cf. Rosin.]

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).

Note: Resins exude from trees in combination with essential oils, gums, etc., and in a liquid or semiliquid state. They are composed of carbon, hydrogen, and oxygen, and are supposed to be formed by the oxidation of the essential oils. Copal, mastic, quaiacum, and colophony or pine resin, are some of them. When mixed with gum, they form the gum resins, like asafetida and gamboge; mixed with essential oils, they frorm balsams, or oleoresins.

Highgate resin (Min.), a fossil resin resembling copal, occuring in blue clay at Highgate, near London.

Resin bush (Bot.), a low composite shrub (Euryops speciosissimus) of South Africa, having smooth pinnately parted leaves and abounding in resin.

Source: Webster's Revised Unabridged Dictionary (1913)