a. [f. BOAT v. or sb. + -ABLE: app. first in U.S.] Navigable by boat.
1683. Penn, Descr. Pennsylv., Wks. 1782, IV. 315. The Schuylkill being an hundred miles boatable above the Jules.
1796. Morse, Amer. Geog., I. 536. The boatable waters of the Allegany.
1807. Vancouver, Agric. Devon (1813), 383. Where the tidal waters flow, and are always boatable.
1864. Marsh, Man & Nat., 420. A boatable channel.