What does impassable mean?
Impassable is an adjective meaning that something cannot be passed through, crossed, entered, or overcome. It is most often used of physical obstacles such as roads, mountains, rivers, barriers, and difficult terrain, where conditions make movement impossible. The word can also have a figurative meaning: an impasse, obstacle, or problem may be described as impassable when it prevents progress and admits no practical solution. “Impassable” tends to sound formal and emphatic, suggesting a more complete or formidable obstruction than terms such as difficult or blocked. It is useful when describing a situation in which the normal route or method is unavailable. The related terms passable and impassability express the opposite idea and the quality of being impassable, while related words such as passage, pass, and bypass share the same historical root.
adjectiveNot passable or impossible to cross, enter, or proceed through. It may also refer to an obstacle that cannot be overcome, whether physical, legal, or figurative.
- Not passable or impossible to cross, travel through, or enter.
- In figurative use, too difficult or formidable to overcome, such as an impassable barrier to progress.
"The heavy snow turned the mountain pass into an impassable wall of ice."
"Floodwater made the normally busy road impassable."
"The committee faced an impassable barrier to reaching an agreement."
When a road is truly impassable, it has crossed from inconvenience into principle: there is no way through.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does impassable come from?
Impassable entered English in the early 17th century from French impassable, a word based on Latin impassabilis, meaning “not passable.” The Latin formation uses the prefix in- and the adjective passabilis, related to passare, “to pass.” English words such as pass, passable, passage, and bypass belong to the same broader Latin root and reflect the central idea of moving across or through something.
Related word forms
How impassable is actually used
The word is formal and often conveys a strong sense of complete obstruction. In physical contexts it is especially associated with roads, terrain, barriers, and natural obstacles; in figurative contexts it is commonly used with words such as barrier, obstacle, and problem.
Easily confused with impassable
Impassable describes something that cannot be crossed or proceeded through, whereas impossible describes something that cannot be done or achieved.