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 billion dollars, beaten by a lint trap.

From MarketWatch • May 21, 2026

Users have pointed out that the American flag decal on the phone’s case does not display the flag properly, showing 11 stripes instead of 13 to represent the Thirteen Colonies.

From Salon • May 21, 2026

Thirteen others are also being observed there, while two are at Emory University in Atlanta.

From Los Angeles Times • May 14, 2026

One afternoon as the Under Thirteen Fugees were running, Luma heard the boys cackling and shouting.

From "Outcasts United: An American Town, a Refugee Team, and One Woman's Quest to Make a Difference" by Warren St. John