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

Binge drinking, which increases the risk of breast and several other types of cancers, is also becoming more common among women in their thirties and forties, Siegel notes. —Lisa Rapaport, EverydayHealth.com, 21 Jan. 2025

Basing their findings on an analysis of more than 5,000 start-up entrepreneurs across 44 countries, the report’s authors argue that more needs to be done to enable women in their late thirties and early forties to pursue their social entrepreneurship ambitions. —Trevor Clawson, Forbes, 19 Jan. 2025

Sally, who’s in her forties, is cared for by her mother and seemingly slips away with an eerie placidity. —The New Yorker, 17 Jan. 2025

Craig stars as William Lee, an American expat in 1950s Mexico City in his late forties and leading a solitary life amidst a small American community. —Jill Goldsmith, Deadline, 29 Nov. 2024

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