Definition
The formation of words by letters in a written instrument; orthography as applied to legal documents. In law, the operative principle is that incorrect spelling does not vitiate a written instrument—whether contract, deed, indictment, or other document—provided the intention of the parties or the meaning of the text can be ascertained with reasonable certainty from the instrument as a whole.
Common Language
Modern common usage (Wiktionary): The act of forming words from letters; the gerund or present participle of "spell."
Historical common usage (Webster's 1913): "The act of one who spells; formation of words by letters; orthography."
The common and legal meanings are nearly identical in scope, but the legal treatment adds a substantive rule that common usage does not suggest: a misspelled word is not a nullity. Where ordinary readers understand a misspelling to simply be an error, courts historically treated it as a potential defect in a legal instrument. The doctrine that bad spelling does not vitiate resolves that question—common usage assumes the reader will infer the correct word; the law had to say so explicitly.
Why It Matters in Research
Researchers encounter spelling as a legal term primarily in two contexts: (1) challenges to the validity of contracts, deeds, or wills where a word is misspelled; and (2) challenges to indictments or other criminal process where a name or critical term is rendered incorrectly.
The governing principle—that bad spelling does not vitiate when intent is clear—is stable and consistent across historical sources, but its application has shifted. In early common law, formal instruments were scrutinized more strictly for technical defects, and a misspelling in a penal instrument or indictment carried greater procedural risk than it would today. Researchers working in pre-19th-century materials should be alert to cases where a spelling irregularity was used as grounds for demurrer or motion in arrest of judgment—arguments that largely disappeared as courts adopted more liberal rules of construction.
The cross-reference Anderson's provides to IDEM SONANS is the critical navigational pointer. Most substantive legal doctrine associated with spelling defects in names and words is located under that doctrine, not under "spelling" as a standalone entry. A researcher who finds only the spelling entry in a historical digest and stops there will miss the bulk of the relevant authority.
Jurisdictional variation in historical sources is modest on the general principle but more pronounced in criminal procedure. Some historical jurisdictions were stricter about spelling in indictments, particularly for proper names, and the idem sonans doctrine developed partly to address those challenges.
Historical Dictionary Support
The four source dictionaries are in agreement on the core rule: incorrect spelling does not vitiate a written instrument if intent is clear. Black's (both editions) states this tersely and identically. Bouvier elaborates with illustrative examples—"threty" held to mean thirty; "seutene" held to mean seventeen—and notes the rule extends even to indictments, citing Cro. Jac. 607 and 10 Co. 133a. These examples usefully anchor the doctrine in the reality of handwritten instruments, where spelling inconsistency was far more common than in printed text.
Anderson's departs from the others by simply redirecting to IDEM SONANS, which reflects a sound editorial judgment: the legal content of most spelling disputes collapses into that doctrine when the contested word is a name. The historical dictionaries collectively treat "spelling" as a thin entry that points toward deeper doctrine elsewhere, and researchers should read it that way.
What the historical sources do not address is the modern statutory and procedural context. Contemporary rules of civil and criminal procedure generally codify the principle that technical defects in pleadings, including spelling errors, do not require dismissal absent prejudice. The historical common-law rule and the modern procedural rule reach the same destination by different routes.
Encyclopedia Cross-Reference
See Law Mind Encyclopedia: Idem Sonans; Contracts — Construction and Interpretation; Indictments — Formal Sufficiency