compulsory

This term carries a heavy weight of authority and obligation. It suggests an external force, such as a government, a school board, or a legal code, that removes personal choice from the equation. The feeling is one of necessity and strict adherence to a system. While similar to mandatory, compulsory often appears in official, institutional, or legal settings. It describes a requirement that must be fulfilled to avoid a penalty or to satisfy a prerequisite, creating a sense of non-negotiable duty rather than a mere suggestion or strong recommendation.