defensible
 oxford
 views  updated May 11 2018de·fen·si·ble  / diˈfensəbəl/ •
adj. 1. justifiable by argument: a morally defensible penal system.2. able to be protected: a fort with a defensible yard at its feet.DERIVATIVES: de·fen·si·bil·i·ty / diˌfensəˈbilitē/ n.de·fen·si·bly / -blē/ adv.
 The Oxford Pocket Dictionary of Current English