Definition
Dependency carries two distinct legal meanings that operate in almost entirely separate fields of law.
1. TERRITORIAL LAW: A dependency is a territory that belongs to a sovereign state and is subject to its governance, but is geographically and politically distinct from the sovereign's home country. The territory is not a colony — it was not settled by citizens of the mother state — and is not a mere possession held by right of conquest alone. It is held by a recognized legal title, typically treaty or cession, and subject to whatever laws and regulations the sovereign chooses to prescribe.
2. FAMILY AND TAX LAW: Dependency refers to the legal status of a person — typically a child or other qualifying individual — who relies on another for financial support and who may be claimed by the supporting party for legal or tax purposes. In modern usage, this meaning dominates in domestic relations law and in federal tax law, where "dependent" is a defined term with specific qualifying criteria governing who may be claimed and by whom.
Common Language
Modern common usage (Wiktionary): A state of dependence or reliance; a colony or territory subject to external rule; the status of being a legal dependent; reliance on a habit-forming substance.
Historical common usage (Webster's 1913): The state of being dependent or subordinate; a thing that hangs from or is attached to something else as a consequence.
The common definitions capture both the territorial and relational senses reasonably well. The legal gap worth noting is narrower than in many terms, but significant in two directions: in territorial law, "dependency" is a formal classification with constitutional and jurisdictional consequences distinguishable from "colony" and "possession" — distinctions that ordinary usage collapses entirely. In family and tax law, "dependency" is a technical status governed by specific statutory tests, not simply a factual condition of financial reliance.
Recognized Forms
/SUBTYPES
TERRITORIAL DEPENDENCY: A territory under sovereign authority but neither a settled colony nor a conquest possession. Historical examples include territories held by the United States between acquisition and statehood or organized territorial status. The classification carries implications for which constitutional provisions apply and what rights inhabitants hold.
LEGAL DEPENDENT (FAMILY/TAX): A qualifying individual whose financial support relationship to another person is recognized by law, triggering rights (custody, support obligations) or tax benefits (exemptions, credits, filing status). Modern federal tax law defines "dependent" through two tracks — the "qualifying child" and "qualifying relative" tests — each with distinct criteria for age, residence, support, and income.
Why It Matters in Research
Researchers face two distinct navigational problems depending on which sense of the term appears in historical sources.
For territorial dependency: Historical legal dictionary definitions are uniformly focused on this meaning, reflecting the primary usage in the nineteenth century when questions of imperial and colonial governance were legally live. Any researcher working with pre-twentieth-century materials will find "dependency" almost exclusively in this sense. The critical distinctions — dependency vs. colony vs. possession — have constitutional significance and were the subject of genuine legal controversy, particularly in cases involving territories acquired by the United States after 1898 (the Insular Cases line). Researchers should not import modern tax-law connotations when reading historical sources using this term.
For family and tax dependency: This meaning is almost entirely absent from the historical shelf dictionaries represented here, which predate modern income taxation and the detailed statutory architecture governing dependents. Researchers using the Law Mind corpus for tax research must look to statutory sources and regulatory materials, not common law or historical dictionaries. The relevant encyclopedia entries on this topic (tax_12, tax_172, tax_57) provide the framework for the tax-law meaning.
Cross-corpus trap: A search for "dependency" in the corpus will surface both meanings indiscriminately. Context — particularly date and subject matter — is the essential filter.
Historical Dictionary Support
All four shelf sources agree on the territorial definition and follow substantially the same formulation, tracing to United States v. The Nancy, 3 Wash. C. C. 286, Fed. Cas. No. 15,854 — a real judicial source cited explicitly in Black's 2nd edition. The three-part distinction (dependency vs. colony vs. possession) is consistent across all sources: a colony is settled by citizens of the mother state; a possession is held by conquest alone; a dependency is held by recognized legal title but without citizen settlement. Bouvier's and Black's both reproduce this structure. Rapalje & Lawrence is somewhat compressed, noting the title-other-than-conquest requirement and the absence of citizen settlement, but arrives at the same substantive boundary.
None of the historical sources address the family-law or tax-law meanings. This is not a failure of the dictionaries — it reflects the state of the law at time of publication. Federal income taxation at the rates and complexity that generate extensive "dependent" litigation postdates these texts.
The Webster's 1913 entry is consistent with the relational/subordination sense but does not resolve either the territorial or tax meaning with useful precision.
Jurisdictional Note
In U.S. constitutional law, the status of an unincorporated territory as a dependency has implications for which constitutional protections apply to its inhabitants — a question extensively litigated but never fully settled. In tax law, the definition of "dependent" is a federal statutory matter; states vary in how they adopt or adapt the federal definition for state income tax purposes.
Encyclopedia Cross-Reference
Child and Dependent Care Credit — Tax Encyclopedia (tax_12)
Standard Deduction Dependents Limited — Tax Encyclopedia (tax_172)
Exclusions: Dependent Care Assistance — Tax Encyclopedia (tax_57)