Ro·man law n: the legal system of the ancient Romans that includes written and unwritten law, is based on the traditional law and legislation of the assemblies, resolves of the senate, enactments of the emperors, edicts of the praetors, writings of the jurisconsults, and the codes of the later emperors, and that is the basis for much of the modern civil law systems
Merriam-Webster’s Dictionary of Law. Merriam-Webster. 1996.