Although the synonyms canon and regulation have a similar meaning, in non-religious usage, the canon proposes a principle or rule of conduct or procedure that is generally accepted as a valid guide. The words command and prescription can be used in similar contexts, but commandment usually suggests something deliberative rather than obligatory, usually communicated through teaching. In some situations, the words rule and regulation are roughly equivalent. However, the rule applies to more limited or specific situations. Although the words law and regulation have much in common, law implies the imposition of sovereign authority and the obligation of obedience on the part of all those subject to that authority. Some common synonyms for regulation are canon, law, ordinance, command, rule, and law. Although all of these words mean “a principle that governs action or procedure,” regulation implies regulation by authority to control an organization or system. The words law and regulation are synonymous, but differ in nuances. In particular, law implies a law promulgated by a legislative body.

Although in some cases it is almost identical to the order, the order applies to an order that regulates certain details of the procedure or conduct applied by a limited authority such as a municipality.