What is the meaning of Devoir?

Duty, business; something that one must do.

duty

exercise, assignment (set for homework)

must, to have to, should (as a requirement)

must

should

must, to do or have with certainty

to owe (money, obligation and etc)

(even) if it is necessary (+ infinitive)

to have a duty to

devoir

to have to; must

to owe

debt

Source: wiktionary.org