impassable

[ im-pas-uh-buh l, -pah-suh- ]

/ ɪmˈpæs ə bəl, -ˈpɑ sə- /

not passable; not allowing passage over, through, along, etc.: Heavy snow made the roads impassable.

unable to be surmounted: an impassable obstacle to further negotiations.

(of currency) unable to be circulated: He tore the bill in half, making it impassable.

Origin of impassable

First recorded in 1560–70; im-² + passable

im·pass·a·bil·i·ty, im·pass·a·ble·ness, noun im·pass·a·bly, adverb

Unwisely, he took a shortcut and so missed the impassable Cabora Bassa cataracts blocking the river.

Dr. Livingstone, I Presume? The Victorian Explorer at 200 |Tim Jeal |March 19, 2013 |DAILY BEAST
Like a quietly heroic astronaut-to-be from Wapakoneta, Ohio, now gone, they have similar dreams that “nothing is impassable.”

Fire In Cairo: A View From the Arab Street |John Kael Weston |September 20, 2012 |DAILY BEAST
Our beach path was impassable, we found another way on the back road.

Our Visit From Irene |India Hicks |August 27, 2011 |DAILY BEAST
Many roads throughout Europe are impassable—Northern Ireland, Scotland and Wales are particularly stricken.

European Travel Breakdown |Clive Irving |December 20, 2010 |DAILY BEAST

German found the old road blocked up with fallen rocks, so as to be impassable.

The Lives of the Saints, Volume II (of 16): February |Sabine Baring-Gould
In the south, however, this ancient custom still remains in full force; the doors there are yet impassable to lovers.

A Jar of Honey from Mount Hybla |Leigh Hunt
The idea of caste as an eternal and impassable barrier has largely determined the history of India.

The Group Mind |William McDougall
In fact, an impassable gulf yawned between the old Roman religion and modern Roman thought.

Ten Great Religions |James Freeman Clarke
Souls reach out to each other across the impassable gulfs of individual being.

The Spinster Book |Myrtle Reed

impassable

/ (ɪmˈpɑːsəbəl) /

(of terrain, roads, etc) not able to be travelled through or over

impassability or impassableness, noun impassably, adverb