triathlon

noun

tri·​ath·​lon trī-ˈath-lən How to pronounce triathlon (audio)
-ˌlän
nonstandard -ˈa-thə-
Synonyms of triathlonnext
: an athletic contest that is a long-distance race consisting of three phases (such as swimming, bicycling, and running)

Examples of triathlon 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.
Back in the water The operation was timed to be ready for the Olympic triathlon and marathon swimming events. — Camille Knight, CNN Money, 4 July 2026 There are many different ways to take active vacations including niches such as white water rafting, surfing schools, yoga retreats, and triathlon training camps. — Larry Olmsted, Forbes.com, 29 June 2026 To shopping editors, Amazon’s Prime Day events are the bi-annual triathlon of capitalism. — Kate McGregor, Architectural Digest, 27 June 2026 At the university, Lincoln Sabini worked on the student farm, was a member of the triathlon sports club and was a swimming instructor with campus recreation. — Sacbee.com, 23 May 2026 See All Example Sentences for triathlon

Word History

Etymology

tri- + -athlon (as in decathlon)

First Known Use

1924, in the meaning defined above

Time Traveler
The first known use of triathlon was in 1924

Browse Nearby Words

triathlete
triathlon
triatic stay
See all Nearby Words

Cite this Entry

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

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Kids Definition

triathlon

noun
tri·​ath·​lon ˌtrī-ˈath-ˌlän How to pronounce triathlon (audio)
: an athletic contest that is a long-distance race consisting of three phases (as swimming, bicycling, and running)

More from Merriam-Webster on triathlon

Thesaurus: All synonyms and antonyms for triathlon

Britannica.com: Encyclopedia article about triathlon

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