1. (noun)duty, responsibility, obligation the 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
2. (noun)obligation the state of being obligated to do or pay something
"he is under an obligation to finish the job"
3. (noun)obligation, indebtedness a personal relation in which one is indebted for a service or favor
4. (noun)debt instrument, obligation, certificate of indebtedness a written promise to repay a debt
5. (noun)obligation a legal agreement specifying a payment or action and the penalty for failure to comply