Authoritative Au*thor"i*ta*tive, a. 1. Having, or proceeding from, due authority; entitled to obedience, credit, or acceptance; determinate; commanding. [1913 Webster]

The sacred functions of authoritative teaching. --Barrow. [1913 Webster]

2. Having an air of authority; positive; dictatorial; peremptory; as, an authoritative tone. [1913 Webster]

The mock authoritative manner of the one, and the insipid mirth of the other. --Swift. [1913 Webster] -- {Au*thor"i*ta*tive*ly}, adv. -- {Au*thor"i*ta*tive*ness}, n. [1913 Webster]

The Collaborative International Dictionary of English. 2000.