Synonyms: prerequisite, requirement
Definition: something that is required in advance
Usage: Latin was a prerequisite for admission
Similar words: obligation, duty, responsibility
Definition: the social force that binds you to the courses of action demanded by that force
Usage: 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: prerequisite
Definition: required as a prior condition or course of study
Similar words: obligatory
Definition: morally or legally constraining or binding
Usage: attendance is obligatory; an obligatory contribution