Definition
The twenty-fourth part of a natural day; a period of sixty minutes. As a legal unit of time, "hour" appears most often in four distinct contexts:
1. Statutory and regulatory time computation. Statutes, court rules, and administrative regulations frequently measure deadlines, notice periods, or response windows in hours rather than days. An "hour" in this context means sixty minutes of clock time, typically running continuously unless the governing rule specifies otherwise (e.g., business hours only).
2. Compensable work time. Under wage-and-hour law — most prominently the Fair Labor Standards Act — an "hour worked" is a term of art meaning time during which an employee is suffered or permitted to work, including certain waiting time, on-call periods, and preparatory activities. This is not simply the clock-hours an employee spends at a worksite.
3. Court and business hours. Legal instruments, court filings, and service-of-process rules often tie obligations to "business hours" or "court hours," limiting or extending deadlines based on whether offices are open. A filing due "by the close of business" raises distinct questions from one due "within 24 hours."
4. Attorney fee calculation. In fee-shifting contexts and lodestar analysis, "hours" refers to the number of billable hours reasonably expended on litigation, a figure courts scrutinize and may reduce for redundancy, excessiveness, or inadequate documentation.
Common Language
Modern common usage (Wiktionary): A unit of time equal to one twenty-fourth of a day (sixty minutes); also used loosely to mean a general period or season, a distance expressible in travel time, or the canonical hours of prayer.
Historical common usage (Webster's 1913): The twenty-fourth part of a day; sixty minutes; the time of day as shown by a timepiece; also a fixed or appointed conjuncture — "the hour of greatest peril," "the man for the hour."
The common and legal meanings share the same core unit (sixty minutes), but the legal meaning diverges sharply in wage-and-hour law: a legal "hour worked" is not simply sixty minutes of clock time but a regulatory determination about compensability that may include time the employee did not consciously spend working and may exclude time nominally spent at work. Researchers who import the ordinary meaning into a wage-and-hour analysis will reach incorrect conclusions.
Common Confusion
"Hours worked" vs. "hours scheduled" vs. "hours paid." These three phrases are not interchangeable under the FLSA. An employee may be scheduled for eight hours, work ten (including unpaid preparatory time the employer knew about), and be paid for seven. Wage-and-hour liability turns on hours worked in the legal sense, regardless of the other two figures. Older sources and non-specialist treatises sometimes blur this distinction.
Why It Matters in Research
The word "hour" is deceptively simple and carries heavy freight across multiple research contexts. Three traps are worth flagging.
First, wage-and-hour research. The FLSA's "hours worked" standard has been elaborated by decades of Department of Labor regulations (29 C.F.R. Part 785) and case law that significantly expands the intuitive meaning of the term. Researchers relying on pre-FLSA sources or general legal dictionaries will find no guidance on compensable waiting time, donning-and-doffing disputes, or de minimis doctrine — all of which turn on the legal definition of an hour worked.
Second, time computation in procedural rules. Federal and state civil procedure rules increasingly specify deadlines in hours rather than days (following the 2009 amendments to the Federal Rules of Civil Procedure, which moved several deadlines from "days" to "hours" to standardize computation). Researchers working with pre-2009 federal materials or with state rules that have not adopted similar amendments should not assume the same computation methods apply.
Third, the lodestar context. When courts evaluate attorney fee petitions, "hours" is a term subject to judicial reconstruction — courts may find that the actual hours billed were unreasonable and substitute a lower figure. Historical research on fee awards must account for this judicial discretion; the "hours" figure in a fee order is a legal finding, not simply a factual record of time spent.
The Anderson's entry directing readers to BUSINESS, DAY, and SERVICE is a useful cross-reference signal: "hour" cannot be understood in isolation from what kind of hours count (business, calendar, court) and for what purpose (service of process, deadline computation, compensation).
Historical Dictionary Support
All five source dictionaries agree on the basic definition: the twenty-fourth part of a natural day, consisting of sixty minutes. The uniformity here is total, and none of the sources add substantive legal content beyond this.
Burrill provides the most textured entry, noting that in the old books (Bracton, Fleta, and Coke's Institutes) an hour was said to consist of forty minutes or moments rather than sixty. Burrill cites Bracton fol. 264, Fleta lib. 5 c. 5 § 31, and 2 Inst. 318, and notes that a footnote in 2 Bl. Com. 140 characterizes the word "forty" in Coke as a misprint — but Burrill observes that Coke was copying from Bracton and Fleta, both of whom plainly use quadraginta (forty). This is a genuine historical curiosity: the medieval legal hour was not the same duration as the modern one, likely reflecting a different system of time division rather than an error. Researchers working with medieval English legal sources should be aware that temporal references may not map onto modern sixty-minute hours.
What the historical dictionaries collectively miss: wage-and-hour law in its modern regulatory form postdates all five sources. None of them address "hours worked" as a term of art, compensable time doctrine, or the lodestar method. These are entirely 20th- and 21st-century legal constructs that a researcher must pursue through statutory and regulatory sources, not the historical lexicon.
Encyclopedia Cross-Reference
Compensable Time — Hours Worked under the FLSA (Law Mind Employment & Labor Law Encyclopedia)
The Lodestar Method — Reasonable Hours x Reasonable Rate (Law Mind Remedies & Equity Encyclopedia)