Definition
In Roman and civil law, the sister of one's great-great-grandmother (atavia soror) — that is, the sister of a great-grandfather's grandmother. The relationship sits six degrees removed from the propositus in the ascending collateral line. Bracton references the term in his treatment of English inheritance law adapted from Roman consanguinity tables, and distinguishes the plain atmatertera from the atmatertera magna, a yet more remote collateral ancestor.
The term belongs to the precise Latin nomenclature developed in Roman law to map every collateral relative through the female line, allowing jurists and courts to determine degrees of kinship for purposes of inheritance, intestate succession, and the calculation of prohibited degrees of marriage.
Common Confusion
The Roman kinship vocabulary is notoriously dense, and atmatertera is easily confused with adjacent terms. Matertera is simply a maternal aunt (mother's sister). Proatertera is a great-grandmother's sister. Abmatertera is a great-grandmother's sister in a slightly different generational framing depending on the civilian source. Atmatertera extends one generation further back still, to the great-great-grandmother's sibling. Researchers encountering any of these terms in historical documents should not assume equivalence — the degree of relationship, and therefore the inheritance consequence, differs with each prefix.
Why It Matters in Research
This term will appear almost exclusively in three contexts within the Law Mind corpus: (1) medieval and early modern treatises on English inheritance law that drew on Roman civil law models, most prominently Bracton; (2) civilian and canon law materials addressing consanguinity, particularly in the context of impediments to marriage; and (3) digest or institutional writings on intestate succession under Roman law or its scholarly reception in continental Europe.
Researchers should be aware that Bracton's use of Roman kinship terms does not map cleanly onto common law inheritance rules as they later developed. Bracton was synthesizing Roman categories onto Anglo-Norman feudal practice, and the degree to which Roman collateral terminology actually governed English intestate succession at the time of his writing is contested among legal historians. Finding atmatertera in a Bracton passage does not mean the term carried operative legal force in English courts — it may reflect Bracton's civilian learning rather than English practice.
In canon law sources, these extended collateral terms matter because the Church's prohibited degrees of marriage reached considerably further than later secular law, and ecclesiastical courts needed precise vocabulary to adjudicate consanguinity claims. A researcher working on medieval marriage litigation or dispensation records should treat the full Roman kinship vocabulary as a working tool.
The term has no practical significance in modern common law jurisdictions. Its appearance in modern legal research is almost entirely historical or comparative.
Historical Dictionary Support
The four source dictionaries are in close agreement on the core definition. Black's (both editions), Burrill, and Rapalje & Lawrence all define atmatertera as the sister of a great-grandfather's grandmother, and all trace the usage to Bracton, folio 68b. Burrill's entry is the most precise in framing the term as belonging to Roman civil law specifically, which is the correct context.
Black's first edition entry contains an apparent editorial error: a passage defining attachment (a form of mesne process) was appended to the atmatertera definition, almost certainly a typesetting artifact. Researchers using that edition should disregard the property-seizure language, which belongs to an entirely different entry.
The distinction Bracton draws between atmatertera and atmatertera magna — noted in Black's and Burrill — suggests that even within this rarefied terminology, further gradations existed for more remote collaterals. Historical sources do not fully elaborate the atmatertera magna relationship, but the modifier magna (great) signals an additional generational remove.
None of the historical dictionaries address the term's function in canon law consanguinity tables or its role in civilian inheritance doctrine beyond the bare Bracton citation. Researchers needing fuller treatment should consult the Digest or institutional civilian sources directly.
Encyclopedia Cross-Reference
See Law Mind Encyclopedia: Consanguinity and Degrees of Relationship; Roman Law of Succession; Bracton and the Civilian Influence on English Law