for·​ty | \ ˈfȯr-tē How to pronounce forty (audio) \
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 How to pronounce fortieth (audio) \ adjective or noun
forty adjective
forty pronoun, plural in construction
fortyish \ ˈfȯr-​tē-​ish How to pronounce fortyish (audio) \ 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

And if men in their forties no longer want to date me, well, that’s a good thing. Melanie Hamlett, Glamour, "Men My Age Wouldn’t Date Me, so I Became a ‘Cougar’," 5 Apr. 2019 Temperatures in the Norwegian Sea are currently in their forties, with morning snow falls and occasional rain. Kyle Mizokami, Popular Mechanics, "U.S. Carriers Are Operating in the Arctic Circle for the First Time in Decades," 22 Oct. 2018 Many female carriers will ultimately choose to have their breasts and ovaries removed by their mid-forties. Pamela Munster, WSJ, "My Father’s Fight Against the Breast-Cancer Gene," 28 Sep. 2018 Couples and solo travelers in their late-thirties and early-forties appreciate the personalized service and boutique amenities. Susannah Rigg, Condé Nast Traveler, "19 Best Boutique Hotels in Mexico City," 27 Feb. 2018 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

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

15 Apr 2019

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


for·​ty | \ ˈfȯr-tē How to pronounce forty (audio) \

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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More from Merriam-Webster on forty

Rhyming Dictionary: Words that rhyme with forty

Spanish Central: Translation of forty

Nglish: Translation of forty for Spanish Speakers

Britannica English: Translation of forty for Arabic Speakers

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).


an enemy or opponent

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