1. Having, or proceeding from, due authority; entitled to obedience, credit, or acceptance; determinate; commanding.
The sacred functions of authoritative teaching. --Barrow.
2. Having an air of authority; positive; dictatorial; peremptory; as, an authoritative tone.
The mock authoritative manner of the one, and the insipid mirth of the other. --Swift.
-- Au*thor*i*ta*tive*ly, adv. -- Au*thor*i*ta*tive*ness, n.
adv : in an authoritative manner; "she spoke authoritatively"
[syn: with authority, magisterially]