a. and sb. [f. BI- pref.2 1 + VALVE, ad. L. valvæ folds of a door, folding-doors.] A. adj.
† 1. Having two leaves or folding parts, as a shutter or door. Obs.
1677. Plot, Oxfordsh., 271. Great bivalve wooden Windows.
2. Zool. Having two shells united by a hinge.
1661. Lovell, Hist. Anim. & Min., Introd. Fishes which are … bivalve, as the Chama, oister, pectines.
1756. C. Lucas, Ess. Waters, III. 123. Several small bivalve shells.
1848. Carpenter, Anim. Phys., 33. The ligament which holds together the shells of the bivalve Mollusca.
3. Bot. (A seed vessel) Having two valves.
1737. Miller, Gard. Dict., s.v. Chelidonium majus, The Flowers … are succeeded by many bivalve Pods.
1794. Martyn, Rousseau’s Bot., xvi. 191. The capsule bivalve.
B. sb. 1. pl. Folding-doors. Obs. exc. Hist.
1832. Gell, Pompeiana, I. ii. 22. Doors seem to have been called bivalves where only formed of two folds.
2. Zool. A molluscous animal having a shell consisting of two halves joined together by an elastic ligament at the hinge, so as to open and shut like a book: such as the oyster, mussel, etc. Also the shell of such animal.
1683. Phil. Trans., XIV. 507. Distinction of shells into Univalves Bivalves and Turbinated. Ibid. (1771), LXI. 230. Four … species, like the sea bivalve.
1847. Carpenter, Zool., § 876. Lamellibranchiata … To this group belong all ordinary bivalves.
1865. Tylor, Early Hist. Man., viii. 192. The refuse-mounds consist of oysters, mussels, and other bivalves.
3. Bot. A bivalve capsule or seed-vessel.
