fifty

noun

fif·​ty ˈfif-tē 

plural fifties

1

: a number equal to five times 10 see Table of Numbers

2

fifties plural : the numbers 50 to 59

specifically : the years 50 to 59 in a lifetime or century

3

: a 50-dollar bill

fiftieth

ˈfif-tē-əth 

adjective or noun

fifty adjective

fifty pronoun, plural in construction

fiftyish

ˈfif-tē-ish 

adjective

Examples of fifty in a Sentence

She is in her fifties.

The bill for dinner came to $43, and she gave him a fifty.

Recent Examples on the Web

Lounging in a mint-condition, fifties-era Herman Miller Eames chair inherited from a grand-uncle with a dubious past in the oil industry. —Madeline Goetz, New Yorker, 4 Sep. 2025

By contrast, older adults—those in their fifties, sixties, and beyond—often score higher on measures of flourishing. —Robert B. Tucker, Forbes.com, 29 Aug. 2025

With the brief resumption of her romance with Aidan over and her grief for Big largely resolved, Carrie could be free again to date and mingle as a fabulous socialite in her late fifties. —Indiewire Staff, IndieWire, 16 Aug. 2025

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

Word History

Etymology

Middle English, from fifty, adjective, from Old English fīftig, from fīftig, noun, group of 50, from fīf five + -tig group of ten; akin to tīen ten

First Known Use

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

Phrases Containing fifty

• fifty-fifty

Rhymes for fifty

• nifty
• shifty
• thrifty
• unthrifty

Kids Definition

fifty

noun

fif·​ty ˈfif-tē 

plural fifties

: a number equal to five times 10 see number

fiftieth

-tē-əth 

adjective or noun

fifty adjective or pronoun