from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Impossible to pass, cross, or overcome: impassable roads; impassable problems.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Incapable of being passed over, crossed, or negotiated.
- adj. Incapable of being overcome or surmounted.
- adj. Not useable as legal tender.
from the GNU version of the Collaborative International Dictionary of English
- adj. Incapable of being passed; not admitting a passage.
from The Century Dictionary and Cyclopedia
- Not passable; that cannot be passed, or passed over: as, an impassable road.
- Synonyms Impervious, impenetrable, pathless.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. incapable of being passed
From im- + pass + -able. (Wiktionary)