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adj. Morally or legally constraining; binding.

adj. Imposing or recording an obligation: a bill obligatory.

adj. Of the nature of an obligation; compulsory: Attendance is obligatory. Mathematics is an obligatory course.

adj. Biology Obligate.

adj. Imposing obligation, morally or legally; binding: an obligatory promise.

adj. Requiring a matter or obligation.

adj. Binding in law or conscience; imposing duty or obligation; requiring performance or forbearance of some act; -- often followed by on or upon.

Imposing obligation; binding in law or conscience; imposing duty; requiring performance of or forbearance from some act: followed by on before the person, formerly by to.

adj. required by obligation or compulsion or convention

adj. morally or legally constraining or binding

"As such it shares with them certain obligatory objectives requiring the Court of Auditors and the other Institutions to "aim to promote its values, advance its objectives, serve its interests, those of its citizens and those of the Member States, and ensure the consistency, effectiveness and continuity of its policies and actions"."

necessary    prerequisite    incumbent on    indispensable    mandatory   

optional   

bill obligatory   

obligingness    obligatorily    obligato    obligee    obliging   

binding    compulsory   

compulsory    mandatory    justifiable    perfunctory    invariable