Tĕn'a-ble, a.

(tĕn'a-bl, 110), a. [Fr. tenable, from tenir, Lat. tenere, to hold.] Capable of being held, maintained, or defended against an assailant, or against attempts to take; as, a tenable fortress.

I would be the last man in the world to give up his cause when it was tenable. W. Scott.