duty-bound

Từ điển Oxford Advanced Learner 8th

ˌduty-ˈbound [duty-bound] BrE NAmE adjective not before noun (formal)
having to do sth because it is your duty
•I felt duty-bound to help him.

• Từ đồng nghĩa / Synonyms:
  duty-bound(p), obliged(p)