Navigable \Nav"i*ga*ble\, a. [L. navigabilis: cf. F. navigable.
   See Navigate.]
   Capable of being navigated; deep enough and wide enough to
   afford passage to vessels; as, a navigable river.
   [1913 Webster]

   Note: By the common law, a river is considered as navigable
         only so far as the tide ebbs and flows in it. This is
         also the doctrine in several of the United States. In
         other States, the doctrine of the civil law prevails,
         which is, that a navigable river is a river capable of
         being navigated, in the common sense of the term.
         --Kent. --Burrill.
         [1913 Webster] -- Nav"i*ga*ble*ness, n. --
         Nav"i*ga*bly, adv.
         [1913 Webster]