in·de·fea·si·ble (ĭn'dĭ-fē'zə-bəl) adj. That cannot be annulled or made void: an indefeasible claim; indefeasible rights. in'de·fea'si·bil'i·ty n., in'de·fea'si·bly adv.
Main Entry: in·de·fea·si·ble Pronunciation: "in-di-'fE-z&-b&l Function: adjective : not capable of being annulled or voided indefeasible right> —in·de·fea·si·blyadverb