-unpassable-

a. Impassable. E. A. Freeman. -- Un*pass"a*ble*ness, n. Evelyn. [1913 Webster]

a. [ Cf. F. passable. ] 1. Capable of being passed, traveled, navigated, traversed, penetrated, or the like; as, the roads are not passable; the stream is passablein boats. [ 1913 Webster ]

His body's a passable carcass if it be not hurt; it is a throughfare for steel. Shak. [ 1913 Webster ]

2. Capable of being freely circulated or disseminated; acceptable; generally receivable; current. [ 1913 Webster ]

With men as with false money -- one piece is more or less passable than another. L'Estrange. [ 1913 Webster ]

Could they have made this slander passable. Collier. [ 1913 Webster ]

3. Such as may be accepted or allowed to pass without serious objection; adequate; acceptable; tolerable; admissable; moderate; mediocre. [ 1913 Webster +PJC ]

My version will appear a passable beauty when the original muse is absent. Dryden. [ 1913 Webster ]