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.

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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

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determiner

1. 1. amounting to fifteen

      fifteen jokes

   2. ( as pronoun )

      fifteen of us danced

Fifteen ² British  

/ ˈfɪfˈtiːn /

noun

1. history the Jacobite rising of 1715

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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

“Summerset has delivered a 19% compound annual growth rate in net tangible assets per share over the last fifteen years and is still growing its unit base 10% per year,” analyst Will Twiss says.

From The Wall Street Journal • Mar. 3, 2026

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

Around fifteen years ago, he and his collaborators were among the first to entangle the spins of extremely cold atoms.

From Science Daily • Jan. 26, 2026

“By early childhood most high-income nations vaccinate against roughly a dozen to fifteen serious pathogens,” the group said.

From Barron's • Jan. 5, 2026

All told, more than two hundred miles of roads, fifteen miles of highway, two hundred homes, and forty-three bridges were ruined.

From "Mountain of Fire" by Rebecca E. F. Barone