Definition
Affins is a Law French term meaning persons related by marriage — that is, persons connected not by blood but through the marriage of one to a blood relative of the other. It is the plural noun form of the relational concept underlying affinity. In historical legal usage, affins identified those individuals whose relationship to a party was legally significant by reason of marriage rather than consanguinity.
The term appears primarily in older common law sources in connection with two contexts: (1) the law of marriage impediments, where marriage between affins within certain degrees was prohibited; and (2) the law of fines and real property proceedings, where the relationship of parties by marriage could affect standing, interests, or procedural rights.
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Common Confusion
Burrill's entry for AFFINS runs together several distinct legal concepts — kindred by marriage, appellate affirmance of a lower court judgment, solemn affirmation in lieu of oath, and averment — that happen to share the root "affirm" or a similar Latin or Law French stem. These are unrelated legal concepts. The relational term affins (kindred by marriage) should not be confused with:
- AFFIRMANCE: the appellate act of confirming a lower court's judgment
- AFFIRMATION: a solemn declaration substituting for an oath
- AVERMENT: a positive assertion in pleading
The convergence in Burrill is a typographical or editorial artifact of alphabetical dictionary arrangement, not a signal that these terms share legal meaning.
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Why It Matters in Research
Researchers encountering affins in historical documents — particularly in medieval and early modern English legal sources, ecclesiastical court records, or property conveyances — should read it exclusively as a term of relationship by marriage. The term will appear in contexts involving:
- **Marriage prohibition analysis**: Canon law and early common law prohibited marriage between affins within specified degrees. Ecclesiastical courts had jurisdiction over these questions, and affins appears in that literature with some regularity.
- **Fines and real property**: Burrill cites West's Symboleography and Crompton's Jurisdiction, both sixteenth-century practitioners' texts, for the term's use in fines proceedings. Affins in that context identifies parties whose marital connection to a principal party is relevant to the proceeding.
- **Jurisdictional traps in historical sources**: Because Burrill places the marriage-relation sense of affins adjacent to entries for affirmance and affirmation, researchers scanning the dictionary alphabetically may misread the entry. The marriage-relation definition governs any use of the term affins in property or ecclesiastical records.
The term is obsolete in modern legal drafting. Contemporary sources use affinity, relatives by marriage, or in-laws. Researchers working with post-nineteenth-century materials are unlikely to encounter affins except in quoted historical text.
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Historical Dictionary Support
Burrill is the primary English-language legal dictionary source for this term. He traces affins to Law French and cites Kelham's Law French dictionary, West's Symboleography (part 2, title Fines, section 152), and Crompton's Jurisdiction (folio 166) — all authoritative secondary sources for sixteenth-century English practice. The citation trail is specific and reliable.
Burrill does not elaborate on the degrees of affinity to which affins might extend, nor does he address the ecclesiastical-law dimensions of the term. Researchers needing the substantive law of affinity — what relationships it encompasses, how degrees were calculated, how canon law and common law diverged — will not find it under this entry and must consult treatises on marriage law directly.
No comparable entry appears in standard modern legal dictionaries, confirming that the term has passed out of active legal use.
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Jurisdictional Note
The term and its underlying concept of affinity as a marriage impediment operated primarily in English ecclesiastical courts before jurisdiction over marriage passed to civil courts. Civilian and civil law traditions used analogous Latin terminology. American law inherited the concept through common law reception but dispensed with the Law French vocabulary entirely.
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Encyclopedia Cross-Reference
The Law Mind Family Law Encyclopedia — Marriage: Capacity to Marry (Age, Consanguinity, Affinity): Covers the substantive law governing affinity as an impediment to marriage, the degree calculations used under canon and common law, and the modern statutory treatment of marriage prohibitions based on relationship by marriage.
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