Synonyms for Responsibility (same or very similar meaning)
WordNet sense 1 (the proper sphere or extent of your activities):
province
WordNet sense 2 (a form of trustworthiness; the trait of being answerable to someone for something or being responsible for one's conduct):
responsibleness
WordNet sense 3 (the social force that binds you to the courses of action demanded by that force):
duty, obligation
From the ODE community, based on WordNet
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