DEFEASIBLE Meaning of DEFEASIBLE in English [ dɪ'fi:zɪb(ə)l ]■ adjective chiefly Law & Philosophy open in principle to revision, valid objection, forfeiture, or annulment.Derivativesdefeasibility noundefeasibly adverb Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004