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adj. Obligatory; required: a compulsory examination.

adj. Employing or exerting compulsion; coercive.

n. Sports An element, such as a dive or school figure, required of all competitors in an athletic competition. Often used in the plural.

adj. Required; obligatory; mandatory

adj. Having the power of compulsion; constraining

n. Something that is compulsory or required.

adj. Having the power of compulsion; constraining.

adj. Obligatory; enjoined by authority; necessary; due to compulsion.

Exercising compulsion; tending to compel; compelling; constraining: as, compulsory authority; to take compulsory measures.

Obligatory; due to or arising from compulsion; enforced or enforceable; not left to choice.

Done under compulsion; resulting from compulsion.

n. That which has the power of compelling; constraining authority.

adj. required by rule

"The term compulsory, if it has any meaning at all, means that the person has no choice about it."

obligatory   

optional   

constraining    obligatory    necessary   

voluntary    mandatory    subsequent    temporary    obligatory    strict    federal    legislative    self-imposed    penal