What is the meaning of duty?

noun

• 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
  • synonyms: responsibility, obligation
• Work that you are obliged to perform for moral or legal reasons.
  • usage: "the duties of the job"
• A government tax on imports or exports.
  • usage: "they signed a treaty to lower duties on trade between their countries"
  • synonyms: tariff