Definition
1. (adjective) Lawful; in accordance with law or established legal requirements. In this broadest sense, a legitimate act, authority, or government is one that derives its validity from legal recognition or established legal process.
2. (adjective, family law) Born in lawful wedlock, or subsequently given the legal status of one so born. A legitimate child is one born to parents who were legally married at the time of birth, or who has been legitimated by subsequent act. Legitimacy in this sense determines a child's legal relationship to the father, rights of inheritance, claims to support, and standing in succession.
3. (verb, archaic) To legitimate. To confer the status of legitimacy upon a child born outside of marriage — placing that child on the same legal footing as one born in wedlock. Distinguished from adoption, which creates a new legal relationship; legitimation recognizes and regularizes an existing biological one.
Common Language
Modern common usage (Wiktionary): In accordance with the law; conforming to accepted rules or standards; authentic; genuine; also, relating to hereditary rights or lawful birth.
Historical common usage (Webster's 1913): Accordant with law or established legal forms; lawfully begotten; born in wedlock; authorized; real; not false or spurious.
Editorial note: The ordinary English meaning of "legitimate" has broadened significantly in everyday use — it now covers anything genuine, reasonable, or defensible, well beyond its legal core. The legal meaning is narrower and more technical in two distinct registers: in public law, legitimacy speaks to the lawful basis of authority; in family law, it speaks specifically to the circumstances of a child's birth and the legal consequences that flow from them. A researcher encountering "legitimate" in historical legal texts should resist the modern colloquial sense and read for which legal register the author is invoking.
Common Confusion
LEGITIMATE vs. LAWFUL: These terms overlap but are not identical. "Lawful" typically means not prohibited by law. "Legitimate" carries the additional sense of conformity with established forms, recognized processes, or hereditary principles — a nuance that matters in succession disputes and constitutional history.
LEGITIMATE vs. LEGITIMATED: A child born in wedlock is legitimate by birth. A child born outside marriage who is subsequently recognized under applicable law is legitimated — the process conferring legitimate status after the fact. Historical sources sometimes use "legitimate" loosely to cover both conditions; careful researchers should check whether the text describes status at birth or acquired status.
LEGITIMATION vs. ADOPTION: Legitimation recognizes the legal relationship between a biological parent and child; adoption creates a legal relationship where none (or a different one) existed. The distinction mattered enormously in inheritance law and still appears in intestacy analysis.
Recognized Forms
/SUBTYPES
Legitimate birth: Status acquired at birth by virtue of the parents' valid marriage.
Legitimation by subsequent marriage: In many jurisdictions and under Roman law (Inst. 1.10.13), a child born before the parents' marriage acquires legitimate status upon their subsequent valid marriage.
Legitimation by judicial or legislative act: A formal proceeding or statute conferring legitimate status, recognized in civil law systems and some common law jurisdictions by statute.
Why It Matters in Research
Historical sources use "legitimate" in the family law sense far more than modern materials, where the term has largely migrated into constitutional and administrative law discourse. Researchers working in probate, intestacy, and family law records before the mid-twentieth century will encounter legitimacy as a threshold question — one that controlled inheritance rights, name, domicile, and support obligations. Courts and commentators of earlier periods were not writing in the modern idiom of "legitimacy" as a political science concept.
The corpus shift matters: in nineteenth- and early twentieth-century case law and treatises, "legitimate issue" and "legitimate heirs" are terms of art in succession documents. In constitutional and administrative law materials from the mid-twentieth century forward, "legitimate government interest" and "legitimate purpose" emerge as terms of art in equal protection and due process analysis — a completely different legal register.
Jurisdictional variation in legitimation law is significant. Civil law jurisdictions (and states with civil law heritage) historically followed Roman law principles, including legitimation by subsequent marriage. Common law jurisdictions were historically stricter — English common law did not recognize subsequent marriage as legitimating prior-born children, a divergence that produced different results in American states depending on their statutory inheritance frameworks.
Researchers using Westlaw or Lexis full-text searches on "legitimate" will retrieve an enormous volume of constitutional and administrative law results unless the search is focused. Adding family-law-specific terms or date-restricting to the period in question will sharpen results considerably.
Historical Dictionary Support
Bouvier and Burrill are in close agreement: both define legitimate in its adjectival sense as "lawful" or "lawfully born," and both treat the verb to legitimate as meaning to confer on a child born before marriage the legal standing of one born within it. Both cite the same Vermont authority (26 Vt. 653) for this proposition, suggesting a shared source base for the operative illustration.
Burrill adds the Roman law grounding — citing Justinian's Institutes (Inst. 1.10.13) for the principle of legitimation, which is useful for tracing the civil law lineage of the doctrine. Neither dictionary addresses the constitutional or public law usage of "legitimate" — the sense of lawful governmental authority or legitimate state interest — which was not yet the prominent legal usage in their era. Researchers relying solely on these historical dictionaries for constitutional research will find the entries incomplete.
Neither dictionary distinguishes sharply between legitimacy as a status and legitimation as a process, treating the verb form somewhat loosely. Modern family law draws that line with more precision.
Jurisdictional Note
Under English common law, subsequent marriage did not legitimate a child born before it — a rule that persisted in some American states well into the twentieth century. Most American jurisdictions have since adopted statutes following the civil law rule or the Uniform Parentage Act framework, which substantially altered how legitimacy is established and what consequences attach to it. Researchers analyzing historical succession disputes should identify which rule the relevant jurisdiction applied at the time of the decedent's death, not at the time of research.
Encyclopedia Cross-Reference
Law Mind Encyclopedia — Legitimacy
Law Mind Encyclopedia — Parent and Child
Law Mind Encyclopedia — Succession and Inheritance