Open English Wordnet
Nouns
(n)duty, responsibility, obligationthe social force that binds you to the courses of action demanded by that force“we must instill a sense of duty in our children”, “every right implies a responsibility; every opportunity, an obligation; every possession, a duty” (John D.Rockefeller Jr)
(n)obligationthe state of being obligated to do or pay something“he is under an obligation to finish the job”