Definition
A Latin term from medieval and early English law meaning to assure, or to make secure by pledges or by solemn interposition of faith. The word functioned as a verb describing the act of binding oneself — or another — to a course of conduct or obligation through a formal commitment of faith or honor, rather than through a modern contractual mechanism. It appears in legal instruments, royal writs, and ecclesiastical records where a party gave formal assurance of performance, safe conduct, or fidelity.
The term carries two intertwined senses that frequently appear together:
1. To give security or assurance by pledge — a material commitment backed by something of value or by personal honor.
2. To bind by solemn interposition of faith — an oath-like undertaking, often without a tangible pledge, grounded in the speaker's sworn word or religious conscience.
Why It Matters in Research
ASSECURARE is an archaic Latin term encountered almost exclusively in pre-modern sources: medieval writs, Year Books, Cowell's Interpreter, Spelman's Glossary, and documents of the ecclesiastical and chancery courts. Researchers will not find it operative in modern legal instruments. Its significance is interpretive: when it appears in a historical document, it signals that the obligation created was grounded in faith and personal honor, which carries implications for how breach would have been remedied — typically through ecclesiastical sanction or chancery equity rather than common law debt or covenant actions.
Be alert to the distinction between assecurare and cognate terms like securare or assurare. Medieval scribes were not uniform in their usage, and documents transcribed or translated in the 17th and 18th centuries sometimes render these interchangeably. When dating a source, consider whether you are reading the original Latin record or a later gloss, as the rendering of assecurare may reflect the interpreter's era as much as the document's own.
The two authorities cited across all three dictionary sources — Cowell and Spelman — are the foundational glossaries for this class of term. John Cowell's Interpreter (1607) and Sir Henry Spelman's Glossarium Archaeologicum (posthumously published, 1664) are the primary lexicographical lineage here. Any researcher who needs fuller context should go directly to those sources rather than relying on the stripped-down dictionary paraphrase.
Historical Dictionary Support
All three dictionary sources — Black's 1st edition, Black's 2nd edition, and Rapalje & Lawrence — converge on the same definition, and all trace back to Cowell and Spelman. There is no meaningful divergence among them. The Rapalje & Lawrence entry is the fullest of the three, adding the phrase "solemn interposition of faith" explicitly and citing both glossaries by name. Black's 2nd edition reproduces essentially the same language. This uniformity signals that none of the 19th-century American dictionaries undertook independent research on the term; they were all channeling the same two 17th-century English glossarists.
What the historical dictionaries do not provide is any illustration of the term in context — no sample writ, no procedural setting, no indication of how a court would have evaluated a failure to assecurare. For that, researchers must go directly to Cowell, Spelman, or to primary records in which the term appears.
Jurisdictional Note
ASSECURARE has no operative role in any modern common law jurisdiction. It appears only in historical legal materials of English and continental European origin. American legal usage never adopted the term as a living part of its vocabulary; its appearance in American dictionaries reflects the 19th-century practice of cataloguing Latin and Law French terms from the English legal heritage rather than terms in active domestic use.