Ratable \Rat"a*ble\, a. 1. Capable of being rated, or set at a certain value. Twenty or[ae] were ratable to [at] two marks of silver. --Camden. 2. Liable to, or subjected by law to, taxation; as, ratable estate. 3. Made at a proportionate rate; as, ratable payments. -- {Rat"a*ble*ness}, n. -- {Rat"a*bly}, adv.