1. A piece of orange or lemon peel, or the aromatic oil which may be squeezed from such peel, used to give flavor to liquor, etc.
2. To cut into thin slips, as the peel of an orange, lemon, etc.; to squeeze, as peel, over the surface of anything.
3. To give a relish or flavor to; to heighten the taste or relish of; as, to zest wine.
4. Hence, something that gives or enhances a pleasant taste, or the taste itself; an appetizer; also, keen enjoyment; relish; gusto. Almighty Vanity! to thee they owe Their zest of pleasure, and their balm of woe. (young) Liberality of disposition and conduct gives the highest zest and relish to social intercourse. (Gogan)
5. The woody, thick skin inclosing the kernel of a walnut.
Origin: F. Zeste, probably fr. L. Schistos split, cleft, divided, Gr, from to split, cleave. Cf. Schism.