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

Jack met with Amir Hassan, a Navy veteran in his early forties who once served on the security detail for the Secretary of Transportation. —Samantha-Jo Roth, The Washington Examiner, 27 Aug. 2025

By the mid-forties, cohesive fire crews began taking shape. —River Selby august 25, Literary Hub, 25 Aug. 2025

Her husband, Luke Beetham, began showing behaviors later linked to autism and ADHD in his mid-forties. —Cheryl Robinson, Forbes.com, 22 Aug. 2025

So, error correction has been around since probably late forties, early fifties. —Quanta Magazine, 7 Aug. 2025

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

Rhymes for forty

• corti
• rorty
• shorty
• sortie
• sporty
• warty
• pianoforte

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