Latin word rationabilis comes from Latin rationem, Latin -abilis (-able; able or worthy to be.)

Detailed word origin of rationabilis

Dictionary entry	Language	Definition
rationem	Latin (lat)
-abilis	Latin (lat)	-able; able or worthy to be.
rationabilis	Latin (lat)	(of a person) rational, capable of reasoning. (of a thing) (Late Latin) agreeable to reason, reasonable.

Words with the same origin as rationabilis