ultramarathon

noun

ul·​tra·​mar·​a·​thon ˌəl-trə-ˈmer-ə-ˌthän How to pronounce ultramarathon (audio)
-ˈma-rə-
Synonyms of ultramarathonnext
: a footrace longer than a marathon
ultramarathoner
ˌəl-trə-ˈmer-ə-ˌthä-nər How to pronounce ultramarathon (audio)
-ˈma-rə-
noun

Examples of ultramarathon in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The woman who keeps beating men in ultramarathons runs on mashed potatoes. — Greg Rosenstein, NBC news, 18 May 2026 Yet an increasing number of endurance athletes are taking on these longer ultramarathons. — Brad Stulberg, Outside, 26 Mar. 2026 All of this could also explain why the performance gap between men and women in ultramarathons is often smaller. — Claire Maldarelli, Scientific American, 2 July 2026 And the ultramarathon got so big that organizers added a 100 mile mountain bike race, which became a big deal in its own right. — Alan Gionet, CBS News, 22 Apr. 2026 See All Example Sentences for ultramarathon

Word History

First Known Use

1964, in the meaning defined above

Time Traveler
The first known use of ultramarathon was in 1964

Rhymes for ultramarathon

See All Rhymes for ultramarathon

Browse Nearby Words

ultramafic
ultramarathon
ultramarine
See all Nearby Words

Cite this Entry

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

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Thesaurus: All synonyms and antonyms for ultramarathon

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