Definition
An obsolete term of old English law with two distinct meanings:
1. Kindred; the state or relationship of cousinship. The term described a blood relationship between persons, particularly within the context of hereditary land claims.
2. A writ of entry in the real actions system, available to an heir when the tresail — that is, the father of the besail, or the great-grandfather of the claimant — died seised of lands in fee simple and a stranger subsequently entered and abated (took wrongful possession of) those lands. The writ of cosenage was one of a sequence of ancestral writs designed to recover land dispossessed from a claimant's lineal ancestors at progressively more remote degrees of relation.
The writ sat within a graduated system: aiel lay for dispossession of a grandfather, besaiel for a great-grandfather's father, and cosenage for the tresail — one generation further removed. Beyond that degree, the more general writ of mort d'ancestor or the broader assize actions applied.
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Common Language
Modern common usage (Wiktionary): An obsolete spelling of cozenage — itself meaning the act of cheating, deceiving, or defrauding another; trickery or fraud.
Historical common usage (Webster's 1913): Directs the reader to "cozenage," defined in that tradition as the practice of cozening; deception; fraud; cheating.
The gap here is significant and a genuine research trap. In common English, cosenage (and its variant cozenage) means fraud or deceit — a meaning wholly unrelated to its legal sense. In old English law, cosenage referred to cousinship and, by extension, to a specific real-property writ grounded in that hereditary relationship. A researcher encountering the word in a legal source must not import the common meaning of fraudulent dealing; the legal term derives from cousinship, not from cozening.
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Common Confusion
COSENAGE / COZENAGE: These spellings look nearly identical and share a phonetic origin, but they carried distinct meanings in their respective domains. Cozenage (common English) = fraud. Cosenage (legal English) = kindred relationship and the associated writ of entry. The confusion is compounded because some historical legal sources and copyists used variant spellings inconsistently. Burrill's Law Dictionary redirects the reader to COSINAGE, which is the more stable legal spelling and should be consulted as the primary form in research.
COSINAGE / COSENAGE / COSINAGE: These are spelling variants of the same legal term, not separate writs. Researchers should cross-check all three spellings when working through period records, plea rolls, or digests.
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Why It Matters in Research
This term presents two layers of risk for corpus researchers.
First, the spelling problem. Cosenage, cosinage, and cognate forms appear interchangeably in medieval and early modern legal records. A word-search limited to one spelling will miss instances recorded under another. Researchers working in plea rolls, Year Books, or Fitzherbert's Natura Brevium — the standard practitioner's reference for the ancestral writs — should search all variant spellings.
Second, the meaning collision with cozenage (fraud). Optical character recognition and transcription errors in digitized historical texts frequently conflate these terms. An entry that appears to describe a fraud action may, on inspection of the original, refer to the ancestral writ. The reverse error is also possible. Always verify against the original source when the surrounding context is ambiguous.
Third, the writ of cosenage is an endpoint in a historical system that was substantially abolished. The real actions — including aiel, besaiel, and cosenage — were progressively curtailed and eventually swept away by English real property reforms in the nineteenth century. Sources post-dating the reforms use the term only in historical or taxonomic discussions, not as a live procedural category. American jurisdictions did not adopt the ancestral writ system in any operative sense; references in American legal dictionaries are descriptive of English legal history only.
For corpus users: the most productive path into this term runs through Fitzherbert's Natura Brevium and Glanvill's treatment of the real actions. Black's (both editions) and Burrill converge on the same definition, suggesting a stable received meaning by the nineteenth century, even though the writ itself was long dead in practice.
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Historical Dictionary Support
Black's Law Dictionary (1st and 2nd editions) offer materially identical definitions, indicating that by the time of Black's compilation the term was purely historical and its contours were settled. Both editions cite Fitzherbert's Natura Brevium at folio 221 as the primary authority — a citation that points researchers to the sixteenth-century practitioner's guide that codified the ancestral writ system for English common lawyers.
Burrill's Law Dictionary adds no independent content, redirecting to COSINAGE — the spelling Burrill evidently treated as canonical. This cross-reference is itself useful: it confirms that cosenage and cosinage were understood as variants, not as distinct terms.
No historical dictionary entry consulted addresses the fraud-meaning collision directly, which is a meaningful gap. Historical legal lexicographers apparently assumed their readers would not confuse a term of art rooted in kinship law with a term of general English usage rooted in deceit. Modern researchers working in digitized corpora cannot safely make that assumption.
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Jurisdictional Note
The writ of cosenage was an English common law action and was never transplanted into American practice as an operative writ. American legal dictionaries include it for historical completeness. Researchers working in English sources should be aware that the real actions system fell into disuse well before the Statute of Real Property (1833) and subsequent reforms effectively abolished what remained.
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Encyclopedia Cross-Reference
Law Mind Encyclopedia — Ancestral Writs (for the graduated system of aiel, besaiel, and cosenage)
Law Mind Encyclopedia — Seisin and Feudal Land Tenure (for the underlying property concepts driving the writ's operation)
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