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fifteen

American  
[fif-teen] / ˈfɪfˈtin /

noun

  1. a cardinal number, ten plus five.

  2. a symbol for this number, as 15 or XV.

  3. a set of this many persons or things.


adjective

  1. amounting to 15 in number.

fifteen 1 British  
/ ˈfɪfˈtiːn /

noun

  1. the cardinal number that is the sum of ten and five

  2. a numeral, 15, XV, etc, representing this number

  3. something represented by, representing, or consisting of 15 units

  4. a rugby union football team

"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

determiner

    1. amounting to fifteen

      fifteen jokes

    2. ( as pronoun )

      fifteen of us danced

"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
Fifteen 2 British  
/ ˈfɪfˈtiːn /

noun

  1. history the Jacobite rising of 1715

"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

Usage

Spelling tips for fifteen The word fifteen is hard to spell because it doesn’t simply combine the spelling of the base number, five, with the suffix -teen, as is done in other easy-to-remember spellings like fourteen and sixteen.  How to spell fifteen: When five is combined with suffixes, the ve is turned into an f: fifteen (not fiveteen), fifty (not fivety), and fifth (not fiveth). Remember: there’s no v in fifteen.

Etymology

Origin of fifteen

before 900; Middle English, Old English fiftene. See five, -teen

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The last mayoral race began shaping up in 2021, when former City Councilmember Joe Buscaino announced he was running about fifteen months before election day.

From Los Angeles Times • Feb. 5, 2026

According to Kpler figures, at least 16.7 million barrels of crude oil were stored on board at least fifteen large tankers, used as temporary reservoirs near the Venezuelan coast, at the beginning of the week.

From Barron's • Jan. 8, 2026

This performance is triple the longest lifetime documented in laboratory experiments and nearly fifteen times greater than the standard used in industrial quantum processors.

From Science Daily • Nov. 17, 2025

Ten, fifteen, or twenty at a time would clutch at the tape, as it streamed out with its endless lines of quotations,” Miller wrote in the Chicago Tribune of Oct.

From The Wall Street Journal • Sep. 28, 2025

“The library will be closing in fifteen minutes,” a voice said.

From "The Way to Rio Luna" by Zoraida Cordova