prerequisite vs duty

prerequisite and duty both are nouns.

Word	Noun	Adjective	Verb	Adverb
prerequisite	Yes	Yes	No	No
duty	Yes	No	No	No

As nouns, duty is a hypernym of prerequisite; that is, duty is a word with a broader meaning than prerequisite:

prerequisite: something that is required in advance
duty: the social force that binds you to the courses of action demanded by that force

Other hypernyms of prerequisite include obligation, responsibility.

prerequisite (noun)	duty (noun)
something that is required in advance	the social force that binds you to the courses of action demanded by that force
	work that you are obliged to perform for moral or legal reasons
	a government tax on imports or exports

prerequisite (adjective)	duty (adjective)
required as a prior condition or course of study