decade

American  

[dek-eyd, duh-keyd] / ˈdɛk eɪd, dəˈkeɪd /

noun

1. a period of ten years.

   the three decades from 1776 to 1806.

2. a period of ten years beginning with a year whose last digit is zero.

   the decade of the 1980s.

3. a group, set, or series of ten.

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decade British  

/ dɪˈkeɪd, ˈdɛkeɪd /

noun

1. a period of ten consecutive years

2. a group or series of ten

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Other Word Forms

Derived Forms

• half-decade
  noun
• decadal
  adjective

Etymology

Origin of decade

First recorded in 1425–75; late Middle English, from Middle French, from Late Latin decad-, stem of decas, from Greek dekás “group of ten”; equivalent to deca- + -ade ²

Explanation

She was so nervous to see her high school sweetheart at their reunion: it had been a decade (ten years) since she'd seen him at graduation, and she still got butterflies thinking about him. A decade is a period of ten years. Decade contains dec, which is used in words that have to do with tens. The Marty Paich Dectet was a band with ten players. A decahedron is a shape with ten faces. And the decimal system is based on the number ten.

Example Sentences

Over the past decade, Lozano's group has tested numerous designs under different operating conditions and with a variety of ionic liquid fuels.

From Science Daily • Jun. 10, 2026

More than a decade later, former EBay chief Meg Whitman spent $144 million of her wealth on her bid to become California’s governor, setting a new national record for spending on a state election.

From Los Angeles Times • Jun. 10, 2026

Almost a decade ago, Nebraska made it easier to recover Medicaid costs.

From MarketWatch • Jun. 10, 2026

Johnson & Johnson Chairman and Chief Executive Joaquin Duato said finding a cure for certain cancers and turning others into chronic diseases is a realistic goal for the coming decade.

From The Wall Street Journal • Jun. 10, 2026

For a decade now, Devaney had sponsored this conference—called ASF, or the American Securitization Forum, in part because it sounded more dignified than the Association for Subprime Lending.

From "The Big Short" by Michael Lewis