Definition
In historical legal usage, *sig* (from the Latin *signum* or *sigillum*) refers to a seal or act of sealing a legal instrument. The term appears in abbreviated Latin maxims and doctrinal writing as a shorthand for the sealing function that, in medieval and early common law practice, authenticated documents and gave them legal force. To *sig* an instrument was to affix a seal — whether a wax impression, a signet ring, or other mark of authentication — conferring validity upon deeds, wills, and other formal writings.
The term is encountered almost exclusively in Latin abbreviation or as part of a longer phrase in early legal sources. It is not a freestanding term of art in modern practice.
Common Language
Modern common usage (Wiktionary): To good-naturedly mock or tease someone; also used in African American Vernacular English in the sense of "to signify."
Historical common usage (Webster's 1913): Urine (provincial English dialect).
Neither common meaning bears any relationship to the legal use. The legal *sig* derives entirely from Latin *signum* (sign, mark) and *sigillum* (seal), and its appearance in legal sources signals a Latin abbreviation or doctrinal shorthand, not an English word in any ordinary sense.
Why It Matters in Research
Researchers encountering *sig* in manuscript sources, early printed law books, or Latin legal maxims should read it as an abbreviation for *signum*, *sigillum*, or a cognate form — not as an English term. Bracton and Fleta, two of the primary medieval authorities, use sealing terminology extensively to define the formal validity of deeds and testaments. Burrill preserves the term precisely because early treatises condensed sealing doctrine into abbreviated Latin phrases that appear without explanation in later digests and case reporters.
The critical research trap is misreading *sig* in a Latin passage as a standalone English legal term with independent definitional content. It has none. Its meaning is always contextual: it marks the presence or absence of a seal, the identity of the sealer, or the legal consequence of sealing with another's instrument.
For testament validity specifically, the Digest passage preserved in Burrill (*Si ab ipso testatore annulum accepero, et signavero, testamentum valet, quasi alieno signaverim*) is instructive: it shows that in Roman law — and by reception through medieval common law doctrine — the physical act of sealing could be performed by a third party using the testator's own ring without invalidating the instrument. This distinction between who physically affixes the seal and whose authority the seal represents has downstream relevance to questions of agency, attestation, and authentication in early deed and testament cases.
Researchers working in Bracton (*De Legibus et Consuetudinibus Angliae*, fol. 38), Fleta (lib. 2 and lib. 3), or early Year Books should treat *sig* notation as an index to sealing doctrine rather than to a discrete substantive rule.
Historical Dictionary Support
Burrill's Law Dictionary is the principal source preserving this term with doctrinal content. Burrill connects it to two functions: (1) the phrase *sig* as shorthand for the authenticating declaration "this writing [bears] my seal," citing Bracton and Fleta; and (2) the act of sealing (*signavero*, *sigillo confirmare*) as a juristic event with legal consequences for the validity of the instrument sealed.
Burrill's entry is brief but precise. He does not attempt to generalize *sig* into a freestanding term of English law, recognizing that its life is in Latin legal writing. The Digest citation (Dig. 28.2) anchors the testament example in Roman law, reflecting the civilian influence on medieval English testament doctrine that ran through canon law and ecclesiastical courts. This is a point Burrill leaves implicit; researchers should note that testament law in England prior to the Statute of Frauds 1677 was substantially shaped by civilian and canonical sources, and that *sig* in testament contexts may track Roman rather than common law rules.
No other major historical law dictionaries (Jacob, Tomlin, Black's early editions) appear to carry this term under *sig* specifically, likely because the relevant doctrine migrated into entries for SEAL, SIGILLUM, DEED, and TESTAMENT by the time those dictionaries were compiled.
Jurisdictional Note
The sealing doctrine to which *sig* refers was substantially modified or abolished in most American jurisdictions during the nineteenth and twentieth centuries, and in England by the Law of Property (Miscellaneous Provisions) Act 1989. Research into modern sealing requirements must account for this transformation; *sig* in its historical sense has no operative modern counterpart.