obligation

Noun

• a legal agreement specifying a payment or action and the penalty for failure to comply

• a written promise to repay a debt

• a personal relation in which one is indebted for a service or favor

• the state of being obligated to do or pay something
  • he is under an obligation to finish the job
    

• the social force that binds you to the courses of action demanded by that force; every opportunity, an obligation; every possession, a duty"- John D.Rockefeller Jr
  • we must instill a sense of duty in our children
    
  • every right implies a responsibility
    

Related words

• Synonyms: 
  debt instrument , certificate of indebtedness , indebtedness , duty , responsibility