forty

noun

for·​ty ˈfȯr-tē 

plural forties

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

4

or 40 US, informal : a forty-ounce bottle or other container of an alcoholic beverage (such as beer or malt liquor)

Kelvin finished his forty in seven or eight long gulps. Tossed the bottle in the median carpeted with brown grass.

—Dave Byrne

… smoking weed and drinking 40s while her kids run loose.

—Jim Schutze

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

According to data from The Department of Health and Human Resources, fibroids are most common in women in their forties and early fifties. —Sandra Rose Salathe, Flow Space, 27 June 2024

The research fellow who met me, Birte, was in her forties, and appeared as if she had been harrowed by her work. —John Ganz, Harper's Magazine, 22 May 2024

Still, millennials, the oldest of whom are now in their early forties, have increased their wealth significantly since the start of the pandemic. —Rachel Ventresca, Fortune, 6 June 2024

Yet some form of national service is essential in strengthening the Arab case for equality in a society whose Jewish men devote three years to the nation’s defense and then continue in reserve duty into their forties. —Yossi Klein Halevi, Foreign Affairs, 11 May 2012

Word History

Etymology

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

First Known Use

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

Phrases Containing forty

• forty-five
• forty-niner
• forty winks

Kids Definition

forty

noun

for·​ty ˈfȯrt-ē 

plural forties

: a number equal to four times 10 see number

fortieth

-ē-əth 

adjective or noun

forty adjective or pronoun

fortyish

-ē-ish 

adjective