The definition of authoritative is someone or something having power, influence or the right to control and make decisions.(adjective)
Authoritative is defined as someone who knows a great deal about a certain subject and who is generally considered an expert.(adjective)
A book written by an expert on certain subject matter is an example of an authoritative book.
See authoritative in Webster's New World College Dictionary
Origin: ML auctoritativus
See authoritative in American Heritage Dictionary 4
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