Definition
"Days" in legal contexts is the plural of "day" as a unit of time, but carries distinct technical meanings depending on whether a statute, contract, rule of court, or instrument uses the term with or without qualification. Three principal legal uses arise:
1. CALENDAR DAYS. Every consecutive day on the calendar, including Saturdays, Sundays, and legal holidays. When a statute or rule specifies a number of "days" without qualification, most modern jurisdictions default to calendar days unless the governing rule provides otherwise.
2. RUNNING DAYS. Consecutive days counted without interruption, including non-business days. The phrase appears most often in maritime and commercial contexts — particularly in charter parties — where "running days" for loading or discharge means the count never pauses for weather, Sundays, or port holidays unless the contract expressly excepts them.
3. JURIDICAL OR COURT DAYS. Days on which courts are open and authorized to transact business. In older practice and some statutory contexts, a period stated in "days" was understood to mean only days on which the relevant legal action could actually be taken, effectively excluding Sundays and court holidays from the count.
The operative distinction in any research question is which category applies: the same numeral — say, "30 days" — yields materially different deadlines depending on which reading governs.
Common Language
Modern common usage (Wiktionary): Simply the plural of "day"; the ordinary units of time in a week or month.
Historical common usage (Webster's 1913): "Days" as the plural of "day," a period of twenty-four hours; also used in the phrase "one's days" to mean one's lifetime.
The legal gap is not about the word's meaning but about its scope. Ordinary usage treats all days as equivalent. Legal usage fractures the concept: a "day" may be a calendar day, a business day, a juridical day, or a running day, and the choice carries deadline consequences. A non-lawyer reading "you have 30 days" assumes calendar time; a lawyer must ask what kind of days the instrument or rule intends.
Common Confusion
The most persistent confusion is between calendar days and business days, and between calendar days and running days. These are not interchangeable:
— Calendar days vs. business days: Modern procedural rules increasingly define "days" to exclude weekends and holidays; statutes and contracts do not always follow suit. Older instruments are especially likely to mean calendar days even when context might suggest otherwise.
— Running days vs. lay days: In maritime practice, "running days" is sometimes conflated with "lay days" (the total days allowed for loading/unloading). Lay days may themselves be running days or working days depending on the charter party's language; the modifier controls.
— Computation rules for the first and last day: Across jurisdictions and instruments, there is persistent disagreement about whether to count the triggering event day itself and whether to count the final day when it falls on a non-business day. This is a distinct question from the type of day involved.
Why It Matters in Research
Deadline research is where "days" does its most consequential work, and historical sources are unreliable guides to modern counting rules. Several traps:
STATUTORY INTERPRETATION SHIFT. Older Massachusetts and New York cases cited by Rapalje & Lawrence treated "days" in a statute as presumptively excluding Sundays in certain contexts — a rule that has largely disappeared from modern codified procedure. Researchers applying 19th-century case law to modern deadlines risk importing an exclusion rule that no longer operates.
RUNNING DAYS IN MARITIME SOURCES. The entry for "running days" in Rapalje & Lawrence cross-references a Massachusetts statute case. Maritime charter party disputes, however, developed their own running-days doctrine that treats uninterrupted calendar counting as the default specifically to prevent disputes over which days were "working" days. The encyclopedia entry on the 30-day immigration filing deadline illustrates how modern courts apply a different, non-maritime counting framework entirely.
DEADLINE JURISDICTIONS IN TAX AND IMMIGRATION. The 90-day period for responding to an IRS Notice of Deficiency and the 30-day window for federal court petitions in immigration cases both use "days" in ways that have been extensively litigated. These are calendar-day counts, but exceptions for weekends and holidays at the terminal end of the period have been codified in federal procedural rules and must be checked against the version of the rule in effect at the relevant time.
CORPUS CONNECTIONS. Law Mind sources covering charter parties and maritime law will use "running days" as a term of art. Tax and immigration sources use unadorned "days" in their deadline language, but practitioners and courts supply the calendar-day default from background procedural rules. Researchers should not read silence about the type of day as resolving the question.
Historical Dictionary Support
Rapalje & Lawrence treats "day" as a reference term rather than a defined entry, marshaling case citations under two sub-heads — "day in a statute" and "day in computation of time" — and separately noting "running days in a statute." This citation-list approach, typical of 19th-century legal dictionaries, reflects that the meaning of "days" was understood to be context-dependent and settled by case law rather than by a fixed definition. The Massachusetts and Kentucky authorities cited address the inclusion or exclusion of the first and last days in statutory counting — a question still litigated today, now largely resolved by rules like Federal Rule of Civil Procedure 6.
What historical dictionaries largely miss: the modern codification of counting rules, the calendar-day default in federal and most state procedural codes, and the specific jurisdictional carve-outs for deadlines falling on weekends or holidays. The historical sources are useful for understanding the pre-codification baseline and for reading older instruments, but they do not reflect the procedural rule frameworks that now govern most deadline questions.
Jurisdictional Note
Federal procedure (FRCP 6) defines "days" as calendar days and provides that when the last day falls on a Saturday, Sunday, or legal holiday, the period runs to the next business day. State rules vary; some jurisdictions exclude weekends and holidays from short periods (under 11 days) but use calendar counting for longer ones. International commercial contracts and maritime instruments may apply yet another framework depending on the governing law clause.
Encyclopedia Cross-Reference
IRS Notice of Deficiency 90-Day Letter (The Law Mind Tax Encyclopedia) — for the specific operation of a calendar-day statutory deadline in a tax context.
Federal Court Review — Standard of Review, Exhaustion, and the 30-Day Filing Deadline (The Law Mind Immigration Law Encyclopedia) — for the 30-day period as a jurisdictional deadline in immigration federal court practice.