Beech Beech, n.; pl. Beeches. [OE. beche, AS. b?ce; akin to D. beuk, OHG. buocha, G. buche, Icel. beyki, Dan. b["o]g, Sw. bok, Russ. buk, L. fagus, Gr. ? oak, ? to eat, Skr. bhaksh; the tree being named originally from the esculent fruit. See Book, and cf. 7th Buck, Buckwheat.] (Bot.) A tree of the genus Fagus. Note: It grows to a large size, having a smooth bark and thick foliage, and bears an edible triangular nut, of which swine are fond. The Fagus sylvatica is the European species, and the F. ferruginea that of America. Beech drops (Bot.), a parasitic plant which grows on the roots of beeches (Epiphegus Americana). Beech marten (Zo["o]l.), the stone marten of Europe (Mustela foina). Beech mast, the nuts of the beech, esp. as they lie under the trees, in autumn. Beech oil, oil expressed from the mast or nuts of the beech tree. Cooper beech, a variety of the European beech with copper-colored, shining leaves.