Definition
In legal usage, "plural" means containing, designating, or consisting of more than one. The term appears most commonly in statutory and documentary interpretation, where courts and counsel must determine whether language written in the singular or plural extends to multiple persons or things, or only to one.
The interpretive rule most closely associated with this term is that the plural number is satisfied by two — meaning that a statutory or contractual term in the plural is met whenever two or more instances are present, and the singular is not thereby excluded. A companion rule, equally important, runs in the opposite direction: words in the plural include the singular unless context requires otherwise, and vice versa. Most modern jurisdictions codify this principle in general construction statutes.
Common Language
Modern common usage (Wiktionary): Referring to more or less than one of something; a grammatical number designating other than a single instance. In English, typically formed by adding -s or -es to a noun.
Historical common usage (Webster's 1913): Relating to, or containing, more than one; designating two or more. Used primarily as a grammatical term.
The gap between common and legal meaning is narrow but practically significant. Ordinary usage treats "plural" as a grammatical descriptor. Legal usage treats it as a rule of construction with interpretive consequences — the question is not just what form a word takes, but what legal effect that form produces when applied to statutes, contracts, deeds, or pleadings.
Common Confusion
PLURAL vs. MAJORITY: Anderson's Dictionary of Law redirects "Plurality" to both BIGAMY and MAJORITY, flagging that the word cluster around "plural" spills into distinct legal concepts. Plural marriage concerns multiple simultaneous spouses; plurality in voting law concerns which candidate received the most votes without necessarily a majority; plural number in construction law concerns grammatical form. These are not interchangeable, and a researcher encountering "plurality" in a historical source must confirm which meaning the author intended.
SINGULAR INCLUDES PLURAL / PLURAL INCLUDES SINGULAR: The interpretive rules operate bidirectionally but are not identical in effect. Statutes of general construction typically provide that both directions apply, but courts have not always applied them symmetrically, particularly in criminal statutes where ambiguity favors the defendant.
Why It Matters in Research
The practical significance of "plural" in legal research is almost entirely interpretive. When reading a historical statute, deed, contract, or pleading, the question of whether a term in the plural binds one party or many — or whether a singular term was intended to reach a class of persons — is answered by the construction rules attached to this concept.
Researchers using Law Mind's corpus of historical legal sources should be aware of two traps. First, older statutes frequently lack general construction clauses. In those instruments, the default rule that "plural includes singular and vice versa" cannot be assumed — courts applied common law rules of construction, and those rules were not uniformly applied. Second, the maxim *pluralis numerus est duobus contentus* (the plural number is satisfied by two) appears repeatedly in historical sources and case annotations. It is a genuine rule of Latin-derived common law reasoning, not merely a dictionary note, and its appearance in a source signals that the drafter or court was addressing a minimum threshold question: does a plural term require three, ten, or some larger number, or is two sufficient?
The cross-reference in Anderson's to BIGAMY is a useful corpus pointer: plural marriage in the historical record is treated as a criminal law matter under bigamy and polygamy headings, not as a family law structural concept. Researchers looking for historical legal treatment of multiple simultaneous marriages should pursue BIGAMY as the primary entry point in period sources.
Burrill's note that "as a right, in the plural number, the singular is included" points to a specific property and rights-interpretation context — where a grant or statute uses plural language ("rights," "parcels," "persons"), historical courts often held this sufficient to pass or bind a single instance.
Historical Dictionary Support
The five source dictionaries are in substantial agreement. Black's (both editions), Rapalje & Lawrence, and Burrill all quote Webster directly for the core definition — "containing more than one; consisting of or designating two or more" — and all cite or quote the maxim from 1 Rolle, 476. This convergence reflects that "plural" in legal dictionaries was treated primarily as a construction-law term, not a substantive doctrine in its own right.
Burrill goes furthest by citing Co. Litt. 369a and the New York case at 20 Johns. R. 693, 727, supporting the rule that a plural term includes the singular in the context of rights and grants. This is the most practically useful elaboration in any of the source dictionaries and points to a line of early common law authority that shaped American construction doctrine.
Anderson's is the outlier — it provides no definition of its own and redirects to NUMBER, BIGAMY, and MAJORITY, suggesting that in Anderson's framework the term was considered too general to define independently. This is a minor coverage gap; researchers relying on Anderson's alone would need to follow those cross-references to reconstruct the construction rule.
None of the historical dictionaries addresses codified construction statutes (such as the Dictionary Act or state equivalents), which ultimately superseded the case-by-case application of the common law maxim in most American jurisdictions.
Jurisdictional Note
Most U.S. jurisdictions have enacted general construction statutes providing that singular terms include the plural and vice versa unless context otherwise requires. Federal law contains this rule at 1 U.S.C. § 1. Researchers working with pre-codification materials, or with jurisdictions lacking such a statute, should not assume the bidirectional rule applies and should consult period sources directly.