1. A reference to being worthy of acceptance , trust, belief, or reliability: The driver gave an authentic explanation to the mechanic of why he had an accident with his car.
2. Etymology: from 1340, "authoritative", from Old French autentique, from Medieval Latin authenticus, from Greek authentikosl "original oe genuine."

Originally from Greek authentikos, it was a derivative of the noun authentes, "doer, master", which was formed from autos, "self" and the base -hentes, "worker, doer, being".