In`de*fea`si*ble (?), a. [Pref. in- not + defeasible: cf. OF. indefaisable.]
Not to be defeated; not defeasible; incapable of being annulled or made void; as, an indefeasible or title.
That the king had a divine and an indefeasible right to the regal power.
Macaulay.
© Webster 1913.