Rĕs'in, n.

n. [Fr. résine, Sp., It., & Lat. resina, probably allied to Gr. ῥητίνη, from ῥέειν, to flow.] A solid, inflammable substance, of vegetable origin, a non-conductor of electricity, and insoluble in water, but soluble in alcohol and in essential oils.

☞ Resins exude from trees in combination with essential oils, and in a liquid or semi-liquid state. They are composed of carbon, hydrogen, and oxygen, and are supposed to be formed by the oxygenation of the essential oils. Copal, mastic, guaiacum, and colophony or pine-resin, are some of them. When mixed with gum, they form the gum-resins, like asafetida and gamboge.