Definition
Averium (also rendered averum) is a term from old English and medieval Latin law denoting a live beast kept for labor — a working animal or draft beast. The word appears in feudal and manorial legal texts to identify the category of animal from which obligations such as heriots were satisfied. The averium was not merely any livestock but specifically a beast of service: the ox, horse, or other creature whose value derived from its capacity to work.
The term appears in fixed phrases that carry precise legal weight in historical sources:
1. Melius averium — the best beast. The finest working animal owned by a tenant, which might be claimed by a lord upon the tenant's death as a heriot.
2. De meliori averio suo, vel de secundo meliori — of his best beast, or his second best. A formula describing the lord's election between the first and second finest beast when satisfying a heriot obligation.
3. Per unicum averium vel per duo — by one beast or by two. A phrase specifying whether a particular obligation or tenure service ran to a single animal or a pair.
---
Why It Matters in Research
Averium is a term of almost purely historical significance. Researchers will encounter it not in modern statutes or case law but in medieval English legal manuscripts, Year Books, Bracton, Fleta, and related feudal sources. Its practical importance lies almost entirely in understanding heriot obligations — the lord's right to claim a tenant's best or second-best beast upon death — and in reading manorial records, land tenure disputes, and the law of villeinage.
The chief research trap is terminological overlap. Averium, averia, and aver appear across different sources and different periods, sometimes interchangeably, sometimes with subtle distinctions. Averia (the plural) is used broadly for cattle or working livestock; aver in Middle English manorial documents can shade toward "draft horse" specifically. A researcher working with translated or transcribed records should verify which form the original uses and whether the source distinguishes the terms.
Because the term's legal life runs through Bracton and Fleta rather than through enacted statute, standard common-law statutory indexes will not surface it. Searches in Law Mind should run through feudal tenure, heriot, and villeinage clusters rather than through property or probate collections.
The heriot connection is the critical corpus link. Averium appears most frequently as the object of a heriot claim, making it inseparable from the law governing what lords could demand from tenants at death. Research into heriot without understanding averium will miss the operational vocabulary of the primary sources.
---
Historical Dictionary Support
Burrill traces averium to the Old French aver (to have) or ouvre (work), a derivation consistent with the beast's defining characteristic: it was the animal a tenant possessed for productive labor. Burrill's entry is brief but precise, collecting the key Bracton phrases — melius averium, de meliori averio suo vel de secundo meliori, per unicum averium vel per duo — and supplying folio references to Bracton and Fleta. The cross-reference to Blackstone's Commentaries (2 Bl. Com. 424) anchors the term in the heriot context.
What the historical dictionaries do not supply is a worked account of how the averium was valued or disputed in practice — that dimension must be pursued through Bracton directly and through manorial court rolls. Burrill's entry functions as a locator and glossary rather than a substantive treatment.
No meaningful divergence exists among historical sources on this term: it is a technical term of art that carries a fixed meaning in the feudal context and does not appear to have migrated into other legal domains.
---
Jurisdictional Note
Averium is a term of medieval English law and has no modern jurisdictional distribution. It does not appear as a functional legal concept in any current common-law jurisdiction. Its relevance is confined to historical English law, primarily pre-1700 manorial and feudal practice.
---
Encyclopedia Cross-Reference
See Law Mind Encyclopedia — Heriot (primary reference for the obligation in which averium most frequently appears); Feudal Tenure (for the broader framework of lord-tenant relations governing beast-service); Villeinage (for the status of tenants whose working animals were subject to such claims).
---