Synonyms of authoritative

Adjective

1. authoritative, important, influential (vs. uninfluential)

usage: having authority or ascendancy or influence; "an important official"; "the captain's authoritative manner"

2. authoritative, classical, classic, definitive, standard (vs. nonstandard)

usage: of recognized authority or excellence; "the definitive work on Greece"; "classical methods of navigation"

3. authoritative, authorized, authorised, official (vs. unofficial)

usage: sanctioned by established authority; "an authoritative communique"; "the authorized biography"

Definition and meaning of authoritative (Dictionary)