authentic in WordNet English dictionary

1. not counterfeit or copied
   "an authentic signature"; "a bona fide manuscript"; "an unquestionable antique"; "photographs taken in a veritable bull ring"
   authentic  bona fide  unquestionable  veritable 
   
2. conforming to fact and therefore worthy of belief
   "an authentic account by an eyewitness"; "reliable information"
   authentic  reliable