Definition
In legal Latin, *crastinum* means "the morrow" or "the day after." The term derives from *cras*, the Latin word for "tomorrow," and appears in historical legal instruments, court records, and pleadings to designate the following day as a deadline, return date, or point of legal reckoning. It functions as a precise temporal marker in formal Latin legal usage, identifying the day immediately succeeding a named day or event.
The closely related form *crastino* (in the ablative, meaning "on the morrow") appears more frequently in actual legal contexts — particularly in phrases designating the return day of writs and court appearances, such as *crastino Animarum* (the morrow of All Souls) or *in crastino* (on the next day). *Crastinum* and *crastino* are grammatical variants of the same root and share functional meaning in legal texts.
Why It Matters in Research
Researchers working with medieval English court records, Year Books, plea rolls, or early Chancery documents will encounter *in crastino* constructions regularly when identifying return days and term dates. English common law courts scheduled writs and appearances by reference to feast days and their morrows, making temporal Latin vocabulary essential for accurate dating of legal events. A document specifying that a party was summoned *in crastino Sancti Michaelis* is placing the return on the day after Michaelmas — a specific, calendrically fixed date that carries procedural significance.
The trap for researchers in historical sources is twofold. First, *crastinum* is rarely used in isolation; it almost always appears in genitive constructions tied to a named feast, saint's day, or legal term. Knowing the term in the abstract is less useful than recognizing it within those set phrases. Second, because English legal calendars ran on ecclesiastical feast days that have themselves shifted or fallen out of common knowledge, identifying the precise calendar date requires cross-referencing the underlying feast — not merely translating the Latin. A researcher who translates *in crastino* as "the next day" without identifying the anchor feast will often be unable to assign a concrete date.
Corpus connections: this term connects closely to the Latin vocabulary of English return days (*dies ad quem*, *dies datus*, *quindena*, *octava*) and to the broader system of legal terms, including Hilary, Easter, Trinity, and Michaelmas terms. Researchers navigating plea rolls or early Year Books should treat *crastinum* as a gateway into that dating apparatus rather than as a standalone term of art.
Historical Dictionary Support
Burrill's Law Dictionary provides the core entry: "*crastinum* — Lat. [from *cras*, tomorrow.] The morrow; the day after. See Crastino." The entry is brief to the point of being a cross-reference rather than a definition, directing users to *crastino* for fuller treatment. This reflects Burrill's general practice with Latin grammatical variants — defining the base concept and routing the reader to the form more commonly encountered in practice.
What historical dictionaries largely leave unstated is the procedural significance of the *in crastino* construction in English common law scheduling. The term appears in sources like Glanvill and Bracton, as well as throughout the plea rolls, in contexts that are procedurally technical. Burrill captures the translation but does not reconstruct the dating system within which the word does its work. Researchers relying solely on the dictionary definition will know what *crastinum* means in the abstract while remaining unprepared to use that knowledge in actual document dating.
Jurisdictional Note
*Crastinum* and its variants are features of Latin legal usage common across medieval European jurisdictions — ecclesiastical courts, civil law jurisdictions, and English common law alike. The specific feast-day system for calculating return days, however, is distinctively English and should not be assumed to map directly onto Continental court calendars or canon law schedules without independent verification.