noun
1.
Synonyms: occasion 3, call, cause, necessity
2.
something one is bound to do or forbear
it is our obligation to obey the law
Synonyms: charge, commitment, committal, devoir, duty, must, need, ought, ||right
Related Word: compulsion, constraint, restraint; burden, requirement, responsibility; business, part, place
Contrasted words: choice, discretion, free will, option; decision, determination, pleasure, will
3.
Synonyms: indebtedness 1, arrearage, debt, liability