Antonyms of adj voidable

1 sense of voidable

Sense 1
rescindable, voidable -- (capable of being rescinded or voided; "the judgment was rescindable"; "voidable contracts")

INDIRECT (VIA revocable) -> irrevocable, irrevokable -- (incapable of being retracted or revoked; "firm and irrevocable is my doom"- Shakespeare)

Similarity of adj voidable

1 sense of voidable

Sense 1
rescindable, voidable -- (capable of being rescinded or voided; "the judgment was rescindable"; "voidable contracts")
       => revocable (vs. irrevocable), revokable -- (capable of being revoked or annulled; "a revocable order")