Definition
An archaic Law French verb meaning to sue, or to bring a legal action against another. The conjugated form siwist (or siwed) means sued, indicating a past-tense use in pleading or record language. The term appears in early English legal proceedings and year book reports as a functional equivalent of the Latin prosequi or the English "to sue," referring to the formal prosecution of a legal claim before a court.
Common Confusion
SIWER should not be confused with the modern English word "sewer" or with unrelated Anglo-Norman terms of similar appearance. The resemblance to ordinary English words is purely phonetic. Researchers encountering siwer or siwist in a medieval English legal record are reading procedural language, not a reference to drainage or infrastructure.
Why It Matters in Research
The primary research value of siwer is recognizing it on sight when reading Year Books or early plea rolls. Law French was the working language of English common law pleading and court proceedings from approximately the Norman Conquest through the seventeenth century, and verbs of action like siwer appear in procedural formulas describing who brought a claim, in what capacity, and at what stage. Misreading or failing to recognize siwer can cause a researcher to misidentify the procedural posture of a case — specifically, whether an action had been formally commenced.
The conjugated form siwist is the form most likely to be encountered in Year Book entries, typically in a narrative description of what a party had done. The citation in Burrill — Yearb. H.1 Edw. — points to a Henry I term Year Book entry from the reign of Edward I or Edward II (the abbreviation H. indicating Hilary term), a period when Law French procedural vocabulary was fully standardized. Researchers working in Year Books of that era should expect this and related Law French verbal forms without modern English equivalents to appear without gloss.
Because this term belongs to the procedural vocabulary rather than the substantive law vocabulary of Law French, it is largely absent from later legal dictionaries that focused on doctrinal terms. Researchers who rely solely on post-seventeenth-century dictionaries will not find it. Burrill's preservation of the term, with its Year Book citation, is one of the few accessible reference points in standard American legal dictionary sources.
Historical Dictionary Support
Burrill's Law Dictionary provides the sole entry among the standard historical dictionaries. The entry is brief — "L. Fr. In old English law. To sue. Siwist; sued." — but precise. It correctly identifies the language register (Law French), the legal context (old English law), and supplies the conjugated form. No equivalent entry appears in Bouvier, Black's early editions, or Jacob's Law Dictionary, which suggests the term fell out of active legal use early enough that later compilers did not find it necessary to include. Burrill's broader coverage of Law French procedural vocabulary makes his dictionary the correct first stop for terms of this class.
Jurisdictional Note
Siwer is specific to the English common law tradition and has no application in civil law jurisdictions or in American law as a live term. It is a historical research term only, relevant to English legal history through approximately the seventeenth century.