Innavigable
A Dictionary of Law · Henry Campbell Black · 1891
A Dictionary of Law
Asapplied to streams, not capable of or suitable for navigation; impassable by ships or vessels, As applied to vessels in the law of marine insurance, it means unit for navigation; so damaged by misadventures at sen us to be no longer capable of making a\\.~ ge.
See 3 Kent, Comm. 823, note.