thirteen

American  

[thur-teen] / ˈθɜrˈtin /

noun

1. a cardinal number, 10 plus 3.

2. a symbol for this number, as 13 or XIII.

3. a set of this many persons or things.

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adjective

1. amounting to 13 in number.

thirteen British  

/ ˈθɜːˈtiːn /

noun

1. the cardinal number that is the sum of ten and three and is a prime number See also number

2. a numeral, 13, XIII, etc, representing this number

3. the amount or quantity that is three more than ten; baker's dozen

4. something represented by, representing, or consisting of 13 units

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determiner

1. 1. amounting to thirteen

      thirteen buses

   2. ( as pronoun )

      thirteen of them fell

Usage

Spelling tips for 13 The word thirteen (13) is hard to spell because it doesn’t simply combine the spelling of the base number (three) with the suffix -teen, as is done in other easy-to-remember spellings like fourteen and sixteen.  How to spell thirteen: When three is combined with suffixes, it transforms from three (a cardinal number) to third (an ordinal number). Then, the d is dropped: thirteen (not thirdteen); thirty (not thirdty). Remember: there's no d in thirteen.

Etymology

Origin of thirteen

before 900; late Middle English thirttene, variant of Middle English thrittene, Old English thrēotēne; cognate with Dutch dertien, German dreizehn, Old Norse threttān. See three, -teen

Example Sentences

Thirteen passengers have fallen ill with the deadly rodent-borne virus after an outbreak on a cruise ship, and others are under quarantine.

From The Wall Street Journal • May 27, 2026

Thirteen percent of people recently cited energy costs as a top financial concern, the same share who were concerned about the cost of owning or renting a home, according to an April poll by Gallup.

From MarketWatch • May 27, 2026

Thirteen of the 26 players who were selected — including midfielders Tyler Adams, Gio Reyna, Christian Pulisic and Weston McKennie — were on the U.S. team in Qatar four years ago.

From Los Angeles Times • May 23, 2026

Thirteen of the 39 signers of the Constitution were from the South, and it’s estimated that 25 delegates to the Constitutional Convention owned slaves.

From Salon • May 14, 2026

“You’re going to District Thirteen based on that? A shot of a bird? You think you’re going to find some new city with people strolling around in it? And that’s just fine with the Capitol?”

From "Catching Fire" by Suzanne Collins