iuris

iuris is the Latin genitive singular of ius, meaning "of the law" or "of a right." In Latin grammar, ius is a neuter noun representing law, right, or strength, and iuris expresses possession or relation, as in phrases describing a particular body of law, such as iuris civilis (of civil law) or iuris naturalis (of natural law). The form appears widely in legal and philosophical Latin texts.

In Roman law and later legal scholarship, iuris served as a productive base for compound terms. Notable examples include iuris gentium (the law of nations), iuris civilis (the civil law), and iurisprudentia (jurisprudence, the science of law). The genitive iuris also participates in modern Latin titles and scholarly works that discuss juristic topics within ancient and medieval contexts.

In modern usage, iuris is typically encountered in historical or philological discussions rather than as an active term in contemporary law. It remains significant for etymology, since many English legal terms derive from ius and its derivatives, including jurist, jurisprudence, and jurisdiction, which trace their lineage to Latin phrases built around ius and iuris. The concept denoted by iuris—law, rights, and their systems—permeates discussions of civil law, natural law, and international law, where Latin phraseology retains influence in scholarly and customary practice.