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

But the book’s most valuable chapter might be the one about Bradley’s teaching in the nineteen-fifties, the section that supplies her with her title. —Brian Seibert, New Yorker, 13 May 2026

But this doesn’t make characters in their forties and fifties old. —Literary Hub, 7 May 2026

Stojka came to painting decades later, in her mid-fifties, with the mission of depicting life in the concentration camps. —Ben Davis, The New York Review of Books, 25 Apr. 2026

Between 1960 and 1990, the median age of members of Congress was in the early fifties. —Samuel Moyn, Harpers Magazine, 21 Apr. 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