for·ty | \ˈfȯr-tē \
plural forties

Definition of forty 

1 : a number equal to four times 10 — see Table of Numbers

2 forties plural : the numbers 40 to 49 specifically : the years 40 to 49 in a lifetime or century

3 : the third point scored by a side in a game of tennis

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Other Words from forty

fortieth \ˈfȯr-tē-əth \ adjective or noun
forty adjective
forty pronoun, plural in construction
fortyish \ˈfȯr-tē-ish \ adjective

Examples of forty in a Sentence

The temperature outside is in the high forties. She is in her forties.

Recent Examples on the Web

Nothing harvests cash from the back forty like big data. Shawn Tully, Fortune, "This Agriculture Giant Is Bringing in the Drones to Modernize Farming From Cornfields to Vineyards," 19 June 2018 On a recent afternoon, Beatrice Fihn, the Swedish antinuclear activist, walked into a Tribeca café to address her next audience: sixty new mothers and about forty of their children, most under three years old. Sophie Brickman, The New Yorker, "Talking Arms Control with Babes in Arms," 7 May 2018 Each posted his highest single-season ERA+ in his thirties (or, for Clemens, his forties), but their numbers there were 226, 159 and 188, respectively. Emma Baccellieri,, "The Unprecedented Brilliance of Justin Verlander," 5 June 2018 Tales for the three in the 1930’s and the four in the forties, golden ages both. Tim Layden,, "It's Instinctive to Compare Justify's Triple Crown to American Pharoah's but Both Share Connection to Greatness," 10 June 2018 It’s hard to imagine such a scheme working, unless Trump establishes a political command over the private sector not seen in America since the forties. Caleb Crain, The New Yorker, "Is Capitalism a Threat to Democracy?," 7 May 2018 Fire personnel pronounced the victim, initially identified as a female in her mid-forties, dead on scene. Jordan Cutler-tietjen, sacbee, "Woman shot, killed in apparent South Sacramento homicide," 8 July 2018 Staff at Bugworks recount stories of friends in their forties dying in hospital from pneumonia, or from a urinary tract infection that lasts months as one antibiotic after another fails to work. Ari Altstedter,, "The Startups Waging War Against Superbugs," 25 June 2018 And can the average amateur athlete learn anything from them to continue competing into her forties and beyond? Graham Averill, Outside Online, "The Secret to Athletic Longevity Is Surprisingly Simple," 17 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'forty.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of forty

before the 12th century, in the meaning defined at sense 1

History and Etymology for forty

Middle English fourty, adjective, from Old English fēowertig, from fēowertig group of 40, from fēower four + -tig group of 10; akin to Old English tīen ten

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Statistics for forty

Last Updated

14 Oct 2018

Look-up Popularity

Time Traveler for forty

The first known use of forty was before the 12th century

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More Definitions for forty



English Language Learners Definition of forty

: the number 40

forties : the numbers ranging from 40 to 49

: a set of years ending in digits ranging from 40 to 49


for·ty | \ˈfȯr-tē \

Kids Definition of forty

 (Entry 1 of 2)

: being four times ten



Kids Definition of forty (Entry 2 of 2)

: four times ten : 40

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Comments on forty

What made you want to look up forty? Please tell us where you read or heard it (including the quote, if possible).


a state of commotion or excitement

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