Authentic

1. Of the same origin as claimed; genuine.
2. Conforming to reality and therefore worthy of trust, reliance, or belief.
3. (music, of a Gregorian mode) Having the final as the lowest note of the mode.
4. (obsolete) authoritative

(of the claimed origin): genuine, real, bonafide, bona fide, unfaked

(conforming to fact): reliable, trustworthy, credible, unfaked

(not of the claimed origin): phony, fake; ingenuine