authoritatively

US /əˈθɔːr.ə.t̬ə.t̬ɪv.li/
UK /əˈθɔːr.ə.t̬ə.t̬ɪv.li/
1.

autoritär

in a way that shows you are confident, in control, and expect to be respected and obeyed:

:
•
He speaks his mind quickly and authoritatively.