English word treaty comes from Latin tractatus

Detailed word origin of treaty

Dictionary entry	Language	Definition
tractatus	Latin (lat)	Management, treatment. Sermon, homily. Touching, handling, working. Treatise, tract.
traiete	Old French (fro)
tretee	Middle English (enm)
treaty	English (eng)	(international law) A binding agreement concluded by subjects of international law, namely states and international organizations.. A formal agreement between two or more states.

Words with the same origin as treaty