Antonyms of adj ascertainable

1 sense of ascertainable

Sense 1
ascertainable, discoverable -- (capable of being ascertained or found out; "ascertainable facts")

INDIRECT (VIA determinable) -> indeterminable, undeterminable -- (not capable of being definitely decided or ascertained)

Similarity of adj ascertainable

1 sense of ascertainable

Sense 1
ascertainable, discoverable -- (capable of being ascertained or found out; "ascertainable facts")
       => determinable (vs. indeterminable) -- (capable of being determined or limited or fixed; "determinable velocities"; "matters determinable by law")