C2 noun /ˌpliːnɪpəˈtɛnʃəri/
plenipotentiary
пленипотенциарий
Meaning
a person invested with full power to act on behalf of another, especially in diplomacy
Example
The ambassador was a plenipotentiary sent to negotiate the treaty.
Посол был пленипотенциарием, направленным для переговоров о договоре.