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

• decadal adjective
• half-decade noun

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

Electric Boat’s head count has steadily climbed over the past decade after the government in 2010 approved plans to build two nuclear-powered submarines a year.

From The Wall Street Journal • Apr. 18, 2026

Mejia, who started driving for Lyft more than a decade ago, said in his early days, he would sometimes make $400 in three hours.

From Los Angeles Times • Apr. 18, 2026

Beijing has alienated most of the other European partners it courted through the so-called 17+1 initiative a decade ago, notes Dimitar Lilkov, a senior research officer at the Wilfried Martens Centre for European Studies.

From Barron's • Apr. 17, 2026

There’s nothing inherently wrong with that, as long as you have both discussed the financial and lifestyle repercussions of retiring nearly a decade earlier than your wife.

From MarketWatch • Apr. 17, 2026

More than a decade later, she told a confidant that the raid “was what one might have expected of Nazi Germany, but not of the United States.”

From "The Woman All Spies Fear" by Amy Butler Greenfield