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

The stock has been higher ten of the last thirteen weeks but still trades 9% below its annual peak.

From Barron's • May 26, 2026

Nevada also joined the group this week, bringing the total number of members to thirteen.

From Los Angeles Times • Sep. 5, 2025

We just got new numbers, and it’s down to one in thirteen, an all-time low.

From Salon • Mar. 26, 2025

We all feel like we've been under water, literally, for thirteen years, and we all just took a breath.

From BBC • Dec. 8, 2024

The window let all the warm air in, and Iremember wondering if it would still be warm thirteen days later when the Cobra came.

From "Firegirl" by Tony Abbott