1. to cease having power, control, or influence over others or a situation
The manager began to lose authority after the scandal was revealed.
O gerente começou a perder autoridade após o escândalo ser revelado.
2. to become less credible or respected in one's position or role
If you make empty threats, you will lose authority with your team.
Se você fizer ameaças vazias, perderá autoridade com sua equipe.