The word authenticity originates from the Greek root “authentikos” (αὐθεντικός), meaning “original, genuine, principal, or authoritative.” It is derived from “authentēs” (αὐθέντης), which literally means “one who acts with authority” or “one who does things for themselves.” The prefix “autos” (αὐτός) means “self,” and “hentes” is related to doing or accomplishing.
The term moved into Latin as “authenticus”, retaining the meaning of “genuine” or “original,” and then into Old French as “authentique” before entering Middle English in the 14th century as “authenticite”.
Thus, the etymology of authenticity reflects the idea of being true to oneself, acting with authority, and maintaining originality and genuineness.