duty

DUTY noun

[ C,U ] uk/ˈdjuːti/ us duty noun [C, U]
(JOB)

B2 something you do as part of your job or because of your position

обязанность
professional/official duties on/off duty
B2 If a doctor, police officer, etc is on duty , they are working, and if they are off duty , they are not working.

быть на дежурстве/не дежурить
I'm on duty tomorrow night.
duty noun [C, U]