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eighteen

American  
[ey-teen] / ˈeɪˈtin /

noun

  • eighteens
    plural
  1. a cardinal number, ten plus eight.

  2. a symbol for this number, as 18 or XVIII.

  3. a set of this many persons or things.


adjective

  1. amounting to 18 in number.

eighteen British  
/ ˈeɪˈtiːn /

noun

  1. the cardinal number that is the sum of ten and eight and the product of two and nine See also number

  2. a numeral, 18, XVIII, etc, representing this number

  3. the amount or quantity that is eight more than ten

  4. something represented by, representing, or consisting of 18 units

  5. (functioning as singular or plural) a team of 18 players in Australian Rules football

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

determiner

    1. amounting to eighteen

      eighteen weeks

    2. ( as pronoun )

      eighteen of them knew

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Noun Inflected Forms

Etymology

Origin of eighteen

before 1000; Middle English ehtetene, Old English eahtatēne; cognate with Old Norse āttjān, German achtzehn. See eight, -teen

Vocabulary lists containing eighteen

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Toeing the government line, Ratcliffe reiterated that tracking emerging technologies has been his highest priority, "right up there with China," since he took office eighteen months ago.

From Barron's Jun. 30, 2026

On her podcast, he said he once told his brother Harry: “When I am eighteen, I will never talk to you ever again.”

From The Wall Street Journal Jun. 9, 2026

We counted eighteen French gendarmes watching them from the shore, declining to intervene.

From BBC Jun. 17, 2025

He travelled eighteen miles but only after ejecting every loose object from the balloon to enable it to launch.

From Salon Nov. 3, 2024

“Wash yourself in the sea! We must make a powerful impression on the dragon. Dragons notice appearances, and you children look eighteen varieties of disgusting.”

From "Impossible Creatures" by Katherine Rundell

“Ooh wee! Yo, Benny, we got steel and eighteens on this one!” he shouted like he was talking about a car.

From "The Boy in the Black Suit" by Jason Reynolds

They had long eighteens upon their forecastles, and their broadside guns were composed of twelves and sixes.

From The Rise of Canada, from Barbarism to Wealth and Civilisation Volume 1 by Charles Roger

Accordingly General Taylor ordered the supply train to be parked at its position and left under the guard of two twelve-pounders and the fatal eighteens which had done such signal service on the 8th.

From History of the War Between Mexico and the United States, with a Preliminary View of its Origin, Volume 1 by Brantz Mayer

The whole number of cannon mounted on the fortress was thirty-one, of these, nine were French twenty-sixes; six English eighteens; nine twelve and seven nine pounders.*

From The Life of Francis Marion by William Gilmore Simms

Six long twenty-fours of the new make, here in front, and two eighteens upon either flank, and I should like to see the whole of the Boulogne flotilla try to take yonder shore by daylight.

From Springhaven : a Tale of the Great War by R. D. (Richard Doddridge) Blackmore

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