To command; to require; as, private individuals are not only permitted, but enjoined by law to arrest an offender when present at the time a felony is committed or dangerous wound given, on pain of fine and imprisonment if the wrong doer escape through their negligence. 2. In a more technical sense, to enjoin, is to command or order a defendant in equity to do or not to do a particular thing by writ of injunction. Vide Injunction.