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Synonyms for Authoritative (same or very similar meaning)

WordNet sense 1 (of recognized authority or excellence):
classical, definitive

WordNet sense 2 (established or widely recognized as a model of authority or excellence):

WordNet sense 3 (having authority or ascendancy or influence):

WordNet sense 4 (sanctioned by established authority):
authorised, authorized

WordNet sense 5 (having official authority or sanction):

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