Definition
A Latin term meaning "of ours" or "our own." In medieval English legal usage, *nostri* appears in two distinct contexts:
1. As a component of formal Latin phrases in royal writs and parliamentary documents, where it signifies the king's council or realm — for example, in the phrase used in old writs of summons to parliament, indicating action taken with or by the advice of "our council."
2. As part of the phrase *leges et consuetudines nostri* — "the laws and customs of ours [our realm]" — used as one of the historic names for the common law of England, referencing the body of law and custom belonging to the realm itself.
The term carries no independent substantive legal meaning on its own; its significance is always relational, anchored to whatever phrase or formula it completes.
Common Confusion
*Nostri* is easily confused with *nostrum*, a superficially similar Latin word meaning "our remedy" or, in common English, a quack medicine or pet scheme. The two words share the same root (*noster*, "our") but are grammatically distinct and appear in entirely different legal and medical contexts. Researchers encountering *nostri* in historical legal documents should not conflate it with *nostrum* or assume any shared legal meaning.
Why It Matters in Research
Researchers working in medieval and early modern English legal sources — particularly patent rolls, writs of summons, parliamentary records, and early common law treatises — will encounter *nostri* embedded in Latin formulae rather than standing alone. Its appearance signals proximity to material about royal authority, council governance, or the foundational character of the common law.
The phrase *leges et consuetudines nostri regni* ("the laws and customs of our realm") is historically significant as one of the older descriptive names for the common law, predating the term *common law* as a standalone phrase in widespread use. Researchers tracing the conceptual origins of common law in Bracton, Fleta, or early Year Books should note that *nostri* in this context is not ornamental Latin — it is a substantive claim about the territorial and customary basis of English law.
In parliamentary and writs history, the phrase *de consilio nostri* or similar constructions marks the formal authorization structure of royal commands. Misreading or skipping over *nostri* in such contexts can cause a researcher to misidentify whether an action was taken by royal prerogative alone or with conciliar advice — a distinction that mattered enormously in constitutional and parliamentary disputes.
The Black's entry helpfully cross-references the Fleta passage on *de æquitate*, though the connection is not immediately obvious; the juxtaposition in the source suggests these were companion formulae appearing in proximate legal contexts in early treatise literature.
Historical Dictionary Support
Black's Law Dictionary treats *nostri* primarily through its parliamentary writ context, citing Crabb's *English Law* for the usage in writs of summons. Bouvier's takes the broader view, identifying *leges et consuetudines nostri* as one of the recognized names for the common law and directing readers to Rastell and similar early legal dictionaries.
The two sources complement rather than contradict each other — Black's captures the procedural/formulaic use, Bouvier's captures the jurisprudential/descriptive use. Neither source treats *nostri* as a term of art with independent operative legal meaning, which is the correct framing. Both entries are sparse by design: this is a functional Latin word whose legal significance is entirely contextual.
What the historical dictionaries omit is any discussion of how *nostri* functions as a possessive marker of sovereignty — the implicit claim that law belongs to "us" (the realm, the king, the community of the realm) rather than to external authority. That constitutional subtext, visible in the contrast between *nostri* and, say, Roman or canon law frameworks, is not surfaced in either Black's or Bouvier's but is relevant for researchers working on the English common law's self-differentiation from civil law traditions.
Jurisdictional Note
*Nostri* as a legal term is specific to the English common law tradition and its historical Latin formulary. It does not appear as a term of art in American, Scottish, or other legal systems, though American courts and treatises referencing early English common law will encounter it in quoted sources.