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

Instead, doctors typically start women on hormones much closer to menopause, often in the late forties or early fifties. — Tom Gavin, EverydayHealth.com, 12 Aug. 2026

Crisis and controversy have struck the New York Times on many occasions since its founding, in the eighteen-fifties. — Anthony Lane, New Yorker, 10 Aug. 2026

Your fifties are just – man, anything that’s on your mind, go. — Lauryn Overhultz, FOXNews.com, 10 Aug. 2026

Those ‘boys’ are in their late forties and fifties now — a comforting reminder, to parents who may be despairing about enduring another entry in this franchise, that all children eventually grow up. — Caspar Salmon, Variety, 7 Aug. 2026

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