[ fif-tee ]
See synonyms for fifty on
noun,plural fif·ties.
  1. a cardinal number, ten times five.

  2. a symbol for this number, as 50 or L.

  1. a set of this many persons or things.

  2. fifties, the numbers, years, degrees, or the like, from 50 through 59, as in referring to numbered streets, indicating the years of a lifetime or of a century, or degrees of temperature: She lives in the East Fifties. He's in his late fifties. It's going to be in the fifties again today.

  3. Informal. a fifty-dollar bill: He had a fifty and two tens in his wallet.

  1. amounting to 50 in number.

Origin of fifty

before 900; Middle English; Old English fīftig.See five, -ty1 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use fifty in a sentence

  • She had heard in books of girls writing poetry, romance, history—gaining fifties and hundreds.

    The Daisy Chain | Charlotte Yonge
  • During the fifties the celebrated singing master Piccioli was living in Petersburg.

  • His misconception of Piedmontese policy throughout the fifties is a yet stronger illustration of distorted vision.

    The Life of Mazzini | Bolton King
  • He was a man in his fifties, heavy-set, with a stern, swarthy face.

    The Status Civilization | Robert Sheckley
  • Tell us how you managed the Irish Brigade in France in the fifties.

    My New Curate | P.A. Sheehan

British Dictionary definitions for fifty


/ (ˈfɪftɪ) /

nounplural -ties
  1. the cardinal number that is the product of ten and five

  2. a numeral, 50, L, etc, representing this number

  1. something represented by, representing, or consisting of 50 units

    • amounting to fifty: fifty people

    • (as pronoun): fifty should be sufficient

Origin of fifty

Old English fīftig

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012