: a number that is one more than 12 see Table of Numbers
thirteen adjective
thirteen pronoun, plural in construction
thirteenth adjective or noun

Word History

Etymology

Middle English thrittene, from thrittene, adjective, from Old English thrēotīne; akin to Old English tīen ten — more at ten

First Known Use

14th century, in the meaning defined above

Time Traveler
The first known use of thirteen was in the 14th century

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Cite this Entry

“Thirteen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thirteen. Accessed 7 Jul. 2026.

Kids Definition

thirteen

noun
: a number that is one more than 12 see number
thirteen adjective or pronoun

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