the word "treason" entered english in the 13th century from the old french "traïson", meaning "betrayal". this old french term evolved from the latin noun "trāditiōnem", the accusative form of "trāditiō", which literally means "a handing over, delivering up". this latin root is built on the verb "trādere", meaning "to hand over", from "trāns-" (over, across) + "dare" (to give). the semantic journey from the concrete act of "handing over" to the abstract concept of "betrayal" is clear, as betraying an ally or sovereign is figuratively handing them over to an enemy. the modern english meaning specifically crystallized around the crime of betraying one's nation or sovereign, a concept central to feudal and later national law.

the word is a simplex form. it is derived as a whole from the old french "traïson", which itself came from the latin "trāditiōnem" (meaning "a handing over, delivery, betrayal").