Definition
An abbreviation for *ultimo* (Latin: "of the last [month]"), used in legal and commercial correspondence to refer to a day or date occurring in the month immediately preceding the current one. A document dated "the 15th ult." means the 15th day of last month.
The term appears most commonly in older pleadings, contracts, correspondence, and commercial instruments where a past date needed to be referenced without repeating the month by name. Its counterpart abbreviations are *inst.* (*instante*, meaning "of the present month") and *prox.* (*proximo*, meaning "of the next month").
Common Language
Modern common usage (Wiktionary): To use a character's ultimate ability, typically in the context of video gaming.
Historical common usage (Webster's 1913): Webster's 1913 records *ultimo* as meaning "of or pertaining to last month," used in commercial contexts; the abbreviation *ult.* carried the same meaning in everyday business correspondence of the period.
The modern colloquial sense—a gaming term with no connection to time or dates—shares nothing with the legal meaning. A researcher encountering "ult." in historical legal documents should not be distracted by contemporary usage; the term is entirely a creature of Latin-derived dating convention.
Common Confusion
ULT. / INST. / PROX.: These three abbreviations form a system. *Ult.* (ultimo) refers to last month; *inst.* (instante or instant) refers to the current month; *prox.* (proximo) refers to next month. Misreading any one of the three can throw off the dating of a document by one or two months—a meaningful error when reconstructing a timeline of transactions, notice periods, or contractual deadlines.
Why It Matters in Research
Researchers working with nineteenth-century and early twentieth-century legal correspondence, commercial contracts, pleadings, and court records will encounter *ult.* routinely. The abbreviation was standard in commercial practice on both sides of the Atlantic and persisted well into the early 1900s before gradually disappearing from formal usage.
The practical trap: when a document refers to "the 3rd ult." without specifying the year or the current month, the reference is ambiguous unless the document's own date is known. Always establish the document's date of composition before resolving what month *ult.* points to. When documents in a series use *ult.*, *inst.*, and *prox.* interchangeably across multiple letters, the sequence of correspondence itself becomes the key to resolving each reference.
Because the abbreviation appears in commercial instruments as readily as in legal pleadings, researchers in contract disputes, commercial litigation records, and merchant correspondence archives will encounter it as frequently as those working in strictly legal texts.
Historical Dictionary Support
Burrill's Law Dictionary recognizes *ult.* as a standard Latin-derived abbreviation for *ultimo*, consistent with its treatment of other Latin calendar and correspondence conventions. Burrill's treatment is brief because the term was sufficiently common in practice that extended explanation was considered unnecessary for a working lawyer of the period.
The abbreviation's prevalence in Burrill reflects the broader reliance on Latin shorthand in nineteenth-century Anglo-American legal and commercial writing. Historical dictionaries generally agree on the meaning without variation; there is no meaningful divergence across sources on this point. What the historical dictionaries do not address is the ambiguity problem—that *ult.* is only resolvable when the document's own date is known—because practitioners of the era treated this as self-evident.
Jurisdictional Note
Usage of *ult.* was consistent across English-speaking jurisdictions—English, American, and Commonwealth legal and commercial practice all employed the same Latin abbreviation system. Researchers should not expect jurisdictional variation in meaning, though the term faded from use at somewhat different rates across jurisdictions as the twentieth century progressed.