Definition
An archaic legal term for a traitor. Treachour denotes a person who commits treason or betrayal against a sovereign, lord, or state. The term is a variant spelling of "treacher" and belongs to the vocabulary of medieval and early common law, where treason and betrayal carried both criminal and feudal significance. It does not appear in modern legal usage and survives only in historical texts and early legal dictionaries.
Common Language
Modern common usage (Wiktionary): Obsolete spelling of "treacher," meaning a traitor.
Historical common usage (Webster's 1913): Not independently defined; the concept maps to "traitor" — one who betrays a trust or commits treason against a sovereign or country.
The gap between common and legal usage here is minimal in substance but significant in form. Ordinary historical English used "traitor" widely and colloquially. Treachour is the specifically legal and feudal register of that idea, embedded in a system where betrayal of a lord or sovereign carried defined legal consequences — forfeiture, attainder, and death — rather than mere moral censure.
Common Confusion
Treachour, treacher, and traitor are functionally synonymous in historical sources but are not interchangeable in research. Treachour is the archaic legal spelling; treacher is the common variant; traitor is the term that persisted into modern law. A researcher encountering treachour in a historical document is reading the legal register of the period, not a distinct offense or status separate from treason. Do not conflate treachour as a term with treason as a defined offense — treachour names the person, not the act.
Why It Matters in Research
This is a pure historical term. Researchers will encounter treachour only in early English legal texts, Year Books, medieval statutes, or dictionaries compiled from those sources. Its presence in both editions of Black's reflects the historical reach of those volumes rather than any currency the term held in American practice.
Two research traps apply. First, spelling variation is significant: historical sources spell this word inconsistently — treachour, treachor, treacher, trechour — and a single-spelling search will miss occurrences. Full-text corpus searches should account for these variants. Second, the physical layout of the Black's entries is a trap for the unwary: both editions place the definition of TREAD-MILL immediately after TREACHOUR with no clear visual break in some printings, which can cause the tread-mill definition to be misread as continuation of the treachour entry. Researchers using digitized or OCR-processed versions of Black's should verify where one entry ends and the next begins.
The term has no meaningful jurisdictional variation because it was never adopted into American statutory or case law as an operative term. Its relevance is confined to English legal history and the feudal treason framework predating modern codifications.
Historical Dictionary Support
Both editions of Black's define treachour identically and minimally: "A traitor." Neither edition provides authority, citation, or historical context beyond that two-word gloss. This brevity is itself informative — the editors included the term for completeness in cataloguing historical English legal vocabulary, not because it carried active legal meaning at the time of publication.
Neither edition traces the term to its source in Norman-French legal usage, where variants of the word circulated in the feudal law of allegiance and betrayal. Historical dictionaries such as Cowell's Interpreter and Blount's Nomo-Lexicon engage more substantively with the feudal treason vocabulary of this period and would be more productive sources for a researcher needing contextual depth. Black's entries on TREASON provide the doctrinal framework that treachour inhabited.
The inclusion of the tread-mill entry immediately following treachour in both editions of Black's is a recurring editorial artifact worth noting: it reflects alphabetical compression common to the period and should not be read as substantive connection between the entries.