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Compulsory

/kəmˈpʌlsəri/

Something that must be done or is required by law or rules.

Synonyms:

They had made science compulsory for the school certificate.

Modern languages are compulsory too.

Attendance at the seminar is compulsory for all freshmen.

From late Middle English (in the sense using force): from medieval Latin compulsorius, from compuls- ‘driven, forced’, from the verb compellere.

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