defensible (adj.)

c. 1300, "ready and able to fight, able to defend," from Old French defensable, from Medieval Latin defensibilis, Late Latin defensibilem, from Latin defens-, past-participle stem of defendere (see defend). Meaning "capable of being defended" is from late 14c., sense of "contributing to defense" is from c. 1400; that of "that may be vindicated" is from early 15c. Related: Defensibility.