Where does “traiter” come from?

traiter (French) comes from Middle French traicter, from Old French traiter, from Latin tractāre, from Latin tractō, from Latin -tō, from Latin -tus, from Proto-Italic -tus, from Proto-Indo-European -tus — Derives action nouns from verb roots.

traiter (French): to treat; to take care; to process, spray, coat