noun
Usage: usually capitalized R
: the legal system of the ancient Romans that includes the customary or unwritten law and the written law, is based on the traditional law and the legislation of the city of Rome, and in form comprises legislation of the law-making assemblies, resolves of the senate, enactments of the emperors, the edicts or praetorian law, the writings of the jurisconsults, and the codes of the later emperors — see civil law ; compare jus gentium , natural law