DAT

5 definitions found across Law Mind sources

DATAuthored
The Law Mind • 724 words
Definition
DAT is a Latin abbreviation derived from *data* or *datum*, used in Roman law and in later legal instruments following Roman conventions to denote the date of a document. In Roman imperial constitutions and rescripts, the *dat.* clause appearing at the close of the instrument recorded the day, month, and consulship under which the constitution was issued — in effect, the formal dating formula of the imperial enactment. The abbreviation signals when the instrument was "given" (from *dare*, to give), identifying the moment of promulgation. In medieval and early modern legal Latin documents, the same abbreviation continued to serve as a shorthand for the dating clause.
Common Language
Modern common usage (Wiktionary): "dat" appears in informal written English as a pronunciation spelling of "that," used in dialect representation or casual digital communication. Historical common usage (Webster's 1913): Not recorded as a standard English word; treated as dialectal or nonstandard. The gap here is absolute. The colloquial "dat" shares nothing with the legal abbreviation beyond spelling. A researcher encountering *dat.* in a Roman law source, a medieval Latin instrument, or a legal dictionary cross-reference is looking at a technical dating formula, not an informal orthographic variant.
Why It Matters in Research
The principal research value of understanding *dat.* is navigational: when working with the Corpus Juris Civilis — particularly the Code of Justinian — researchers will encounter the abbreviation in the subscription clauses that close imperial constitutions. These subscriptions record *dat.* followed by day, month, place, and consular year. Accurate interpretation of these clauses is essential for establishing the chronology of Roman legislation, which in turn affects questions of priority, revision, and repeal among constitutions addressing the same subject matter. Trap for historical researchers: In older editions and abridgments of Roman law texts, the *dat.* clause is sometimes truncated, edited out entirely, or confused with the *acc.* (*accepta*) clause, which records when a rescript was received rather than when it was issued. These are distinct legal moments, and conflating them distorts the timeline of a constitution's legal effect. In non-Roman sources — medieval charters, ecclesiastical instruments, notarial records — the same abbreviation performs the same function, and its expansion is necessary to reconstruct the document's place in a chronological sequence. Corpus researchers working with translated or digested sources should verify whether a modern edition has silently converted *dat.* clauses into calendar dates or dropped them, since the consulship or regnal year originally recorded may carry independent significance for authenticating a document or establishing which version of a law was in force. *Dat.* also appears in bills of lading and commercial instruments, though in that context the operative word is ordinarily "date" spelled out, and the abbreviation is less common.
Historical Dictionary Support
Burrill's Law Dictionary treats *dat.* primarily as a Roman law term of art, locating it within the formal structure of the imperial constitution and directing readers to the Code of Justinian for examples. Burrill correctly identifies the abbreviation as standing for *data* or *datum* and notes the consulship as the temporal referent — an accurate description of the subscription form used throughout the Justinianic compilation. What Burrill does not address is the broader diplomatic tradition that carried the *dat.* formula into medieval Latin instruments well after the Roman consulship had ceased to function as a dating mechanism. By the Carolingian period and beyond, *dat.* in charters referred to the date of issue in whatever reckoning — regnal year, anno Domini, indiction — the instrument employed. Researchers relying solely on Burrill's treatment may therefore underestimate the abbreviation's reach across the post-Roman legal documentary tradition. No other source dictionaries in the present corpus provide entries for *dat.*, making Burrill the sole historical dictionary authority here.
Jurisdictional Note
This abbreviation operates in the domain of Roman law, medieval legal Latin, and historical document study rather than in any modern national jurisdiction. Its interpretation is a matter of legal history and Latin diplomatic convention rather than of contemporary positive law.
Encyclopedia Cross-Reference
See Law Mind Encyclopedia: Roman Imperial Constitutions; Dating Clauses in Historical Legal Instruments; Code of Justinian — Structure and Sources.
Related Terms
DATA (the expanded form); DATUM; DATE; CONSTITUTIONSIMPERIAL; RESCRIPT; SUBSCRIPTIO; BILLS OF LADING (for the commercial dating context); CONSULSHIP (Roman chronological referent)
DATmain
Burrill's Law Dictionary • 1867
(421) and "the perils of the seas" employed in bills of lading, are convertible terms. 1 Abbotts' Adm. R. 348. An abbreviation of Data or Datum, in the clause at the end of the constitutions of the Roman emperors, showing the day and month when it was given, and in whose consulship. In other words, the date of the constitution. See the Code of Justinian, passim, and see infra, Date. An abbreviation of Data, or Datum, (qq. v.) in old instruments. The Magna Charta of 9 Hen. III. concludes thus: DAT' apud Westmon' undecimo die Februarii, anno regni nostri nono; GIVEN at Westminster, on the eleventh day of February, in the ninth year of our reign. Private instruments concluded in the same way. Dat London, tali die, anno supradicto. Fleta, lib. 2, c. 64, § 3. See Litt. sect. 371. XIII. Kal. Decemb. CP. Justino et Opilione Conss. DAT. Idib. Aug. Constantinop. Constantio II. et Constante Conss. See Cod. passim. The Novels were dated in a similar manner. The abbreviation was sometimes still further abbreviated to D. From this emphatic Latin word DATA (or datum,) the L. Fr. word date seems to have been immediately formed as a name for the whole clause, and afterwards adopted as an English word of more general application. That the earliest use of date was as a French word, appears from the following passages of Britton: Et pur ceo est bone cautele pur ceux que fount faire chartre, que date soit mys del jour, et del lieu, et del an; and therefore it is a good precaution for those who are about to make a charter, [deed,] that the date be put of the day, and of the place and of the year. Britt. c. 39. Par defaute de date est le brefe abatable et vicious; by defect of the date is the writ abatable and faulty. Id. c. 48. The first of these passages is also important as showing the time when dates in deeds began to come into use. The use of this datum clause, or date, was common to a great variety of instruments, public as well as private. See the date of Magna Charta, under Dat' and Data. And see Done, Donees. The style of the literal translation "Given," &c. is still preserved in public instruments requiring greater formality of style, such as proclamations of state: "Dated," &c. being appropriated to private writings. See Datum, Done.
datconj
Wiktionary (English) • 2026
Wiktionary contributorsCC BY-SA 4.0 • via Kaikki
Extracted and formatted for display by Law Mind. Source link opens the current Wiktionary page and its contributor history; it is not a frozen copy of this extract.
Pronunciation spelling of that.
datpron
Wiktionary (English) • 2026
Wiktionary contributorsCC BY-SA 4.0 • via Kaikki
Extracted and formatted for display by Law Mind. Source link opens the current Wiktionary page and its contributor history; it is not a frozen copy of this extract.
Pronunciation spelling of that.
datadv
Wiktionary (English) • 2026
Wiktionary contributorsCC BY-SA 4.0 • via Kaikki
Extracted and formatted for display by Law Mind. Source link opens the current Wiktionary page and its contributor history; it is not a frozen copy of this extract.
Pronunciation spelling of that.

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