In'de-fēn'si-ble, a.

a. [Prefix in, not, and defensible; O. Fr. indéfensible, It. indefensibile, Sp. indefensible, indefendible, indefesable, N. Fr. indéfensible, indéfendible.] Not defensible; not capable of being defended or maintained, vindicated or justified; as, a military post may be indefensible; a bad cause is indefensible.