decade
Pluraldecades
- 1A period of ten years, especially one that runs from a year ending in 0 to a year ending in 9.
Fashion trends from that decade still influence designers today.
Scientists studied climate data spanning several decades.
UsageCommon in a decade ago, over the past decade and for decades (for many years).
Note
Ten years became the usual meaning by shortening: speakers first said a decade of years, then dropped the last two words. The common calendar decade runs from a year ending in 0 and is named by its numbers (the 1960s) or by a nickname such as the Roaring Twenties. Loosely, over a decade just means more than ten years, counted from any point.
Checked 6 Nov 2026 · 3 facts
- The ten-year sense arose by shortening the phrase decade of years. en.wiktionary.org
- The common named decade runs from 0 to 9; ordinal decades counted from the beginning of the AD era run from 1 to 0. en.wikipedia.org
- Decades have numerical names such as the 1960s and nicknames such as the Roaring Twenties. en.wikipedia.org
- 2A group, set, or series made up of ten members or items taken together.
Note
The broadest meaning, and the one all the others narrow down. Nothing in it fixes what is being counted, so older writers could speak of a decade of soldiers as readily as a decade of anything else.
- 3A series of prayers counted on a rosary, usually one Our Father, followed by ten Hail Marys, and ending with a Glory Be.
He finished the first decade and moved his fingers to the next bead.
The congregation prayed several decades during the evening service.
UsageOften a decade of the rosary; people say or pray a decade.
Note
Catholics use this word to count their progress through the rosary. One says a decade, or several, rather than ten Hail Marys, and fingers move bead by bead within each. Five decades make up the familiar chaplet, each paired with one of the mysteries for meditation. The Fatima Prayer at the close is an addition some make and others leave out.
Checked 6 Nov 2026 · 4 facts
- The prayers within a decade are counted bead by bead. usccb.org
- The familiar rosary chaplet consists of five decades. ewtn.com
- Each decade is associated with a mystery for meditation. marquette.edu
- The Fatima Prayer is an optional addition at the end of a decade. ewtn.com
Less common meanings
- 4The interval between two quantities whose ratio is ten to one, as used on logarithmic scales.
The amplifier's response was measured across several decades of frequency.
Each decade on a logarithmic axis represents a tenfold change.
Note
On a logarithmic scale only the ratio counts, not the size of the numbers. From 1.8 to 18 is one decade, and so is the drop from 0.03 to 0.003. Engineers use the word to describe ranges and slopes: an amplifier is tested over several decades of frequency, and gain roll-off is commonly given in decibels per decade.
Checked 6 Nov 2026 · 3 facts
- Spacing on a logarithmic scale depends on ratios rather than absolute numerical differences. graphpad.com
- Both examples span one decade: 18/1.8 = 10, and 0.03/0.003 = 10. e2echina.ti.com
- Amplifier gain roll-off can be expressed in decibels per decade of frequency. developerhelp.microchip.com
- 5A ten-day period, especially as a division of the month in the ancient Egyptian or French Revolutionary calendar.
Under the Revolutionary calendar, each decade ended with a day of rest.
In the ancient Egyptian calendar, each thirty-day month was made up of three decades.
Note
A calendar-maker's unit that took the place of the week. In the French Revolutionary calendar each of the twelve season-named months held three decades, and the tenth day, the décadi, replaced Sunday as the day of rest. Colin Jones's The Great Nation (2002) sets "decades" in quotation marks. That is a useful habit in historical prose, where it keeps the ten-day unit from being read as the span of ten years.
Checked 6 Nov 2026 · 6 facts
- The ten-day decade replaced the seven-day week in the French Revolutionary calendar. napoleon.org
- The calendar had twelve months, each containing three ten-day decades. en.wikipedia.org
- The month names reflected the seasons. napoleon.org
- Décadi was the tenth day and replaced Sunday as the day of rest. en.wikipedia.org
- Colin Jones wrote The Great Nation, first published in 2002. columbia.edu
- Jones puts the ten-day sense of decades in quotation marks. en.wiktionary.org
- 6A division of a literary work consisting of ten parts or books, such as those of Livy's History of Rome.
The first decade of Livy runs from the founding of Rome to its wars with the Samnites.
The third decade of Livy tells the story of Hannibal's war against Rome.
Note
Classical scholarship's term for a block of ten books. It survives mainly through Livy's History of Rome, whose surviving books are still cited by decade, as in the first decade. Outside that setting it is archaic and literary. A modern reader who sees decade alone will take it to mean ten years, so name the work, or say ten books, when the older sense is meant.
Checked 6 Nov 2026 · 3 facts
- A decade can mean a literary work or division consisting of ten books. en.wiktionary.org
- Livy wrote the History of Rome. en.wikipedia.org
- Livy's surviving books are discussed in decades, with first decade denoting books 1–10. en.wikipedia.org
- 7Any of the series of ten consecutive braille characters that share a regular pattern, the first covering the letters A through J.
- 8A set of resistors, capacitors, or similar components switched to select equal increments of an electrical value, usually zero through nine times a base value.
- 9An electronic counting circuit with ten states, representing the decimal digits zero through nine.
Practice
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Origin
This word came through Middle English and Old French from Late Latin "decadem" (a set of ten), which goes back to Ancient Greek "dekás," from "déka" meaning "ten." Its sense of a ten-year span began as a clipping of the phrase "decade of years."
Checked 6 Nov 2026 · 3 facts
- The word came through Middle English and Old French from Late Latin decadem, meaning a set of ten. en.wiktionary.org
- The Latin word derives from Ancient Greek dekás, from déka, meaning ten. en.wiktionary.org
- The ten-year sense originated as a clipping of decade of years. en.wiktionary.org