composed demeanor

Translations
сдержанное поведение
His composed demeanor impressed everyone at the meeting.
Его сдержанное поведение произвело впечатление на всех на встрече.
Definitions
A composed demeanor refers to a calm, self-assured, and controlled manner of behavior or appearance, especially in challenging or stressful situations.
Words
composed

adjective
сдержанный
demeanor

noun
манера поведения