an abundant nonmetallic tetravalent element occurring in three allotropic forms: amorphous carbon and graphite and diamond; occurs in all organic compounds
tending to or capable of propelling; "propellant fuel for submarines"; "the faster a jet plane goes the greater its propulsive efficiency"; "universities...the seats of propulsive thought"
not counterfeit or copied; "an authentic signature"; "a bona fide manuscript"; "an unquestionable antique"; "photographs taken in a veritable bull ring"
conforming to fact and therefore worthy of belief; "an authentic account by an eyewitness"; "reliable information"