Definition
In Roman law, the senate: the supreme deliberative and legislative council of the Roman people. The term carries two senses in legal sources:
1. The governing body itself — the council composed of senior Roman citizens and magistrates that held broad authority over public affairs, finance, foreign policy, and law.
2. The physical place where that body met — though as Burrill notes, the meeting place was more commonly designated by the term curia.
The senatus was not merely an advisory body; in practice it exercised considerable lawmaking authority, particularly through the senatus consultum (a formal decree of the senate carrying the force of law). As Bouvier explains, the consultum mechanism arose from practical necessity: as Rome's citizen population grew too large to assemble, the senate was consulted in place of the people on matters both public and private.
Common Language
Modern common usage (Wiktionary): A governing body in certain universities, particularly in Scottish universities where the academic senate is formally called the senatus academicus.
Historical common usage (Webster's 1913): Not separately defined; treated as a Latinism equivalent to "senate."
The gap between the common and legal meaning is primarily one of context and register. In legal sources, senatus refers exclusively to the Roman institution and its constitutional role in Roman law. The university usage is institutional borrowing, not legal usage, and carries none of the Roman law implications. A researcher encountering senatus in a legal dictionary or civil law treatise should not read it through the lens of modern collegiate governance.
Common Confusion
Senatus is sometimes used loosely as a synonym for senatus consultum, particularly in older secondary literature summarizing Roman law. These are distinct: senatus names the body; senatus consultum names its formal decrees. The confusion matters because senatus consulta had recognized legal force and were treated as a source of Roman law alongside leges (statutes) and responsa prudentium (juristic opinion). References to the senatus alone do not imply any particular legal rule or enactment.
Why It Matters in Research
Researchers working in Roman law, civil law history, or the foundations of Western legal systems will encounter senatus primarily as institutional background rather than as a term with operative modern legal content. The term has no direct analog in common law jurisdictions and does not appear in modern Anglo-American statutory or case law.
Several research traps deserve attention:
First, the double meaning (body versus place) is largely a historical curiosity, but it surfaces in translation contexts. When historical sources describe events occurring "in senatu," the phrase typically means "in the senate" (the body), while the physical space is more precisely curia. Burrill flags this distinction; Black's does not.
Second, researchers tracing the civil law tradition — particularly in Louisiana, Quebec, and mixed jurisdictions — may encounter senatus as part of foundational discussions of Roman legal sources. The senatus consultum is the operative concept there; senatus itself is contextual framing.
Third, the term appears in Calvin's Lexicon Iuridicum (the "Calv." citation common to Black's, Bouvier's, and Burrill's), which is a 17th-century Latin legal lexicon. Researchers relying on that source should be aware it reflects early modern interpretation of Roman institutions, not classical Roman sources directly.
Finally, the Wiktionary university usage occasionally bleeds into general reference works. Legal researchers should be alert to this when using non-specialist sources.
Historical Dictionary Support
The four source dictionaries are in close agreement on the core definition: senatus means the Roman senate and, secondarily, the place where it met. All four cite Calvin (Calvinus, Lexicon Iuridicum) as the primary authority, indicating that their definitions derive from the same early modern source rather than independent analysis.
Burrill adds the most nuance, noting that the meeting-place sense was "more commonly termed curia" and citing Aulus Gellius (Noctes Atticae XVIII.7.5), giving this dictionary the only classical Latin citation among the four. This is genuinely instructive for researchers wanting to trace terminology to Roman primary sources.
Bouvier is the only source that develops the related term senatus consultum within the senatus entry, providing the fuller legal-functional picture. The others treat senatus as definitional background without engaging its operative legal significance.
What historical sources collectively omit: any discussion of the senate's role in different periods of Roman constitutional history (Republic versus Empire), during which its actual power shifted dramatically. Legal dictionaries treat the institution as static. Researchers working with Roman law sources spanning different eras should consult a specialized Roman law treatise or institutional history for that context.
Encyclopedia Cross-Reference
See also: Senatus Consultum (Law Mind Encyclopedia)