obligation

An act or course of action to which someone is morally or legally bound; a duty.

• obligate/ˈɒblɪɡeɪt/(v)使有义务
• obligatory/əˈblɪɡətəri/(adj)强制性的；义务性的
• obliged/əˈblaɪdʒd/(adj)有义务的

• legal obligation
• contractual obligation
• moral obligation
• meet one's obligations
• fail to meet obligations
• binding obligation
• feel obligated
• under no obligation

1. 1.The company has a legal obligation to report any significant safety incidents to the regulator within 24 hours.
2. 2.I feel a moral obligation to speak up, even though it may be personally uncomfortable.

• duty/ˈdjuːti/— something you must do; often moral
• commitment/kəˈmɪtmənt/— a pledge or promise
• responsibility/rɪˌspɒnsɪˈbɪlɪti/— a duty or obligation

from Latin "obligatio" = a binding, from "obligare" (to bind), from "ob-" + "ligare" (to tie)