For something to be described as passable it must be clear of obstructions or able to be navigated. Another definition is for the object or person to be adequate or barely satisfactory. The adverb form makes the word passably, and the noun form is passability. Its opposite is impassable or not able to be passed.
Passible, on the other hand, is when something or someone is able to feel emotion or despair, especially in the sense that the object or person can gain this emotion from something else (i.e., impressionable). It has a noun form which is passibility. Something can also be nonpassible or unable to feel suffering.
These two words can be confusing because it is common for them to be pronounced in the same way. Passable is much more popular that passible. In fact, when we looked for examples for any of the forms of passible, all we found were incorrect spellings of passable.
Examples
“It’s passable.” That’s the official verdict on Houston Texans running back Arian Foster’s British accent, from the point of view of a U.S.-based reporter for the U.K.-based newspaper the Guardian. [Washington Post]
“It seems all minor at this point, just power line issues and the passability of roads,” the official said. [Ithica Voice]
The freezing weather also brought treacherous conditions to roads, with many motorists in Sheffield forced to abandon their cars overnight after snow left roads impassable. [The Guardian]
“The Hobbit: The Battle of the Five Armies,” provides a passably satisfying ending to a franchise that has always seemed a little like a bonus DVD. [Newsday]