Definition
A fine imposed as punishment for the commission of adultery. The term is Latin in origin and appears in historical English and civil law contexts to describe the monetary penalty assessed against a person convicted of adultery. Adulterium is not a substantive offense in modern law but rather a term of art from medieval and early common law describing the fiscal consequence attached to the offense of adultery when prosecuted as a criminal or ecclesiastical matter.
Common Language
Modern common usage (Wiktionary): "Adulterium" has no standard entry in modern English dictionaries; it is a Latin term with no common English usage apart from its derivation of the word "adultery."
Historical common usage (Webster's 1913): Webster's does not carry a separate entry for adulterium, treating adultery as the operative English term.
The gap here is categorical rather than definitional. Where modern speakers understand "adultery" as a moral or relational concept, adulterium in its legal context was specifically the financial penalty extracted by legal authority — a punishment mechanism, not merely a description of the act. A researcher encountering adulterium in a historical text is reading about a fine, not simply a synonym for the offense itself.
Common Confusion
Adulterium is frequently read as a straightforward Latin synonym for adultery. It is not. Adultery (adulterium in Latin) names the act; adulterium in English legal usage names the fine levied for that act. The distinction matters when reading medieval statutes, ecclesiastical court records, or civil law commentaries: the same Latin word carried both meanings depending on context and jurisdiction, requiring careful attention to whether a source is describing the offense or its financial consequence.
Why It Matters in Research
This term appears almost exclusively in historical sources and is effectively absent from modern legal materials. Researchers will encounter it in:
Medieval English statutes and court records, where adulterium appears as a line item in penalty schedules alongside other monetary forfeitures.
Ecclesiastical court materials, where jurisdiction over adultery overlapped with temporal courts and the fine structure differed between the two systems.
Civil law and Roman law commentaries, where adulterium carries its broader Latin meaning as the act itself, not just the penalty — creating a direct interpretive trap for researchers moving between common law and civil law sources in the same research session.
Louisiana materials present a particular complexity. The Louisiana Civil Code's treatment of "adulterous bastardy" (children born of adulterous connections) reflects the civilian tradition in which adulterium denotes the act, not the fine. Researchers using Louisiana sources alongside English common law sources must track which usage is operative.
Bouvier's citation to Barrington's Observations on the Statutes is the most specific historical anchor for the penalty-specific meaning and is the appropriate starting point for anyone tracing the fine's legal basis in English law.
Historical Dictionary Support
The historical dictionaries are in agreement on the narrow point: adulterium in English legal usage means a fine for adultery. Black's (both editions), Bouvier's, and Rapalje & Lawrence all state this without variation or qualification.
Burrill's is the only source that gestures toward etymology, noting the Latin construction from ad and alter — toward another — which illuminates why the same Latin root served for both the act and its penalty across different legal traditions. Burrill does not, however, develop the distinction between the penalty-specific and act-specific usages, which is the more practically important point.
What the historical dictionaries collectively miss is the jurisdictional instability of the term. None of them flags that civil law sources use adulterium to mean the act, not the fine, leaving researchers without a warning about the interpretive split. Rapalje & Lawrence comes closest by including a separate entry for adultery immediately after adulterium and addressing its grounds-for-divorce dimension, but the transition is abrupt and the overlap is not explained.
Encyclopedia Cross-Reference
See Law Mind Encyclopedia: Adultery — Ecclesiastical Jurisdiction and Temporal Courts; Bastardy and Filiation