'Impassable' definitions:
Definition of 'impassable'
From: WordNet
adjective
Incapable of being passed [syn: impassable, unpassable] [ant: passable]
Definition of 'Impassable'
From: GCIDE
- Impassable \Im*pass"a*ble\, a. [Cf. Unpassable.] Incapable of being passed; not admitting a passage; as, an impassable road, mountain, or gulf. --Milton. -- {Im*pass"a*ble*ness}, n. -- {Im*pass"a*bly}, adv. [1913 Webster]