Definition
Occision is an archaic legal term meaning the killing or slaying of a person. Drawn from the Latin *occisio* (from *occidere*, to kill), it appears in early Law French legal texts as a general term for the act of killing, without inherent distinction as to degree or intent. In historical usage, occision served as a broad descriptor encompassing what later law would carefully subdivide into murder, manslaughter, and justifiable or excusable homicide.
Common Language
Modern common usage (Wiktionary): A killing; the act of killing.
Historical common usage (Webster's 1913): A killing; the act of killing. [Obs.]
Both common and legal definitions are essentially identical in meaning, but the shared label of obsolescence is the operative point: occision has no living usage in either ordinary or legal English. Researchers encountering it will find it exclusively in historical legal materials, where its undifferentiated breadth is the meaningful feature — it does not carry the specific intent or degree requirements that modern homicide terminology demands.
Why It Matters in Research
Occision is a term a researcher will encounter, not deploy. It appears almost exclusively in early common law sources and Law French texts — the kinds of materials found in plea rolls, early treatises, and abridgments predating systematic distinctions among homicide categories. Its significance lies in what it does not say: because occision covers the act of killing without specifying malice aforethought, degree, or circumstances, a historical source using the term cannot be read as confirming the presence of what we now call murder in the technical sense.
Researchers working in the Law Mind corpus should be alert to two practical traps. First, when occision appears in translated or paraphrased historical sources, modern editors sometimes render it as "murder" for readability — a translation that imports legal elements the original did not contain. Second, the term's absence in later sources is itself informative: the displacement of occision by more precise terminology (murder, manslaughter, homicide) tracks the gradual refinement of mens rea doctrine in English criminal law. Spotting where that transition occurs in a source can help date or situate the text.
The term connects corpus-wide to materials on early homicide law, the development of the murder/manslaughter distinction, and Law French legal vocabulary more generally.
Historical Dictionary Support
Burrill's Law Dictionary provides the entry with economy: "A killing or slaying," with the illustrative Law French phrase *Murdre est occision de home* (murder is the killing of a man) drawn from Britton, chapter 6. This citation is instructive precisely because of how it uses occision: Britton's author deploys it as the genus of which murder is a species, confirming that even in the early common law, writers understood occision as the broader category. Burrill adds no further analytical content beyond the Latin derivation and the single citation, which is consistent with a term that was already archaic by the time most law dictionaries were compiled.
Webster's 1913 marks the term simply as "[Obs.]" and attributes its usage to Sir Matthew Hale, pointing researchers toward Hale's *Historia Placitorum Coronae* (History of the Pleas of the Crown) as a natural site for the term's appearance in serious legal-historical writing.
No modern legal dictionary of significance includes occision as a live entry. The historical dictionaries agree on definition and obsolescence; there is no meaningful divergence among sources.
Jurisdictional Note
Occision is a term of English common law origin and does not appear as a term of art in any American, Scottish, or civilian jurisdiction. Researchers encountering it in American colonial-era sources are seeing direct inheritance of English legal vocabulary, not independent usage.