duty

noun

1. 1

   work that you are obliged to perform for moral or legal reasons

   the duties of the job

2. 2

   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

3. 3

   a government tax on imports or exports

   they signed a treaty to lower duties on trade between their countries