adjective

1. that can be believed or accepted; trustworthy; reliable an authentic news report
2. that is in fact as represented; genuine; real an authentic antique
3. legally attested or executed, as a deed, affidavit, etc.
4. true to its type; conforming to an original in style, methods, etc. authentic Japanese cooking
5. Obsolete authoritative

Etymology: ME autentike < OFr autentique < LL authenticus < Gr authentikos, genuine < authentēs, one who does things himself < autos, self + -hentēs < IE base *sen-, to prepare, achieve