Antonyms of adj ascendable

1 sense of ascendable

Sense 1
ascendable, ascendible, climbable -- (capable of being ascended)

INDIRECT (VIA scalable) -> unscalable, unclimbable -- (incapable of being ascended)

Similarity of adj ascendable

1 sense of ascendable

Sense 1
ascendable, ascendible, climbable -- (capable of being ascended)
       => scalable (vs. unscalable) -- (capable of being scaled; possible to scale; "the scalable slope of a mountain")