authoritative
//əˈθɒrɪtətɪv//
Adjective
authoritativeCanonical form
more authoritativeComparative
most authoritativeSuperlative
1
Able to be trusted as being accurate or true; reliable and commanding respect.
This dictionary is considered the most authoritative source on English vocabulary.
2
Commanding and self-confident; likely to be respected and obeyed.
The manager spoke in an authoritative tone that made everyone listen.
3
Proceeding from an official source and requiring compliance or obedience.
The government issued an authoritative directive that all businesses must follow.