Definition
An obsolete unit of dry measure used in old English law for corn and grain, understood by historical legal commentators to have been equivalent to one quarter, or approximately eight bushels. The term appears in medieval English legal records and is now purely of antiquarian and historical interest. It has no operative legal meaning in any modern jurisdiction.
Why It Matters in Research
Researchers are most likely to encounter ACHERSET when working with medieval English land records, manorial accounts, agricultural tenancy agreements, or rent obligations expressed in kind rather than currency. When a historical document specifies grain rents or tithes in achersets, treating the term as equivalent to a quarter (eight bushels) follows the consensus of the principal historical legal dictionaries, though the equivalence is explicitly conjectural in the sources themselves — Cowell, cited by both editions of Black's, uses the word "conjectured," and Bouvier uses "supposed." This uncertainty matters: if a research question turns on the precise quantity of grain owed under a historical obligation, the acherset-to-quarter equivalence should not be treated as settled fact without corroboration from the underlying primary source or specialist scholarship in historical metrology.
Within the Law Mind corpus, ACHERSET is unlikely to appear outside of historical and antiquarian contexts. It connects most naturally to research on feudal tenure, manorial law, and the history of agricultural measurement in England. Researchers tracing grain-based rent obligations, customary dues, or tithe disputes in pre-modern English records should be alert to variant spellings and Latinized forms.
Historical Dictionary Support
The four source dictionaries are in close agreement, differing only in degree of caution. Black's (both editions) and Bouvier concur that the acherset was an ancient English measure of grain equivalent to one quarter or eight bushels, each citing or echoing Cowell's Interpreter — the seventeenth-century legal glossary that appears to be the common ancestor of all these entries. Burrill's entry is fragmentary in the available extract but confirms the Latin form achersetus and the identification as a measure of corn or grain. No source claims certainty about the equivalence, and none provides a primary medieval source directly defining the term. The dictionaries are essentially repeating Cowell's conjecture in succession, which is itself a caution: the acherset-to-quarter equation rests on a single early modern authority, not on a chain of independent medieval attestations.
What the historical dictionaries do not address is the regional variation that likely existed in medieval English measures generally. Dry measures in pre-modern England were notoriously inconsistent across counties and commodities, and the "quarter" itself varied by locale and period. Researchers should treat the eight-bushel figure as a working approximation rather than a fixed standard.
Jurisdictional Note
ACHERSET is a term of old English law only. It has no recognized counterpart or survival in Scots law, Irish law, or any jurisdiction outside the medieval English legal tradition. No modern jurisdiction uses or defines the term.