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

Example Sentences

Recent Examples on the Web Plaintiffs in the lawsuit against Kentucky specifically sued over the school’s refusal to add field hockey, triathlon and lacrosse. Rachel Axon, USA Today, 15 Dec. 2022 For one, it has been adopted by a handful of elite triathlon coaches and athletes. Amby Burfoot, Outside Online, 20 Sep. 2021 The best in the world are joining the Milwaukee triathlon scene. Lori Nickel, Journal Sentinel, 26 Jan. 2023 Liz Perry, president and CEO of Travel Juneau, told KTOO Public Media on Friday that an Ironman Alaska triathlon organizer told her the decision arose from economic concerns, including inflation. Chris Bieri, Anchorage Daily News, 11 Dec. 2022 Arizona State triathlon continued its dynasty with its sixth-straight national title on Saturday at Tempe Town Lake. Jenna Ortiz, The Arizona Republic, 12 Nov. 2022 Knopfle’s triathlon coach is Sara McLarty, who excelled in cross country, swimming and track for DeLand High before becoming an All-American swimmer at UF and an accomplished professional tri-athlete. Buddy Collings, Orlando Sentinel, 6 Oct. 2022 Adrian’s first lesson with a triathlon coach was a success, but his enthusiasm was short-lived. Brenda Aréchiga, Los Angeles Times, 30 Sep. 2022 But even in the rarefied air of triathlon, the privileges of Ironman XC can be a sore subject. Devin Gordon, New York Times, 6 Dec. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'triathlon.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History


tri- + -athlon (as in decathlon)

First Known Use

1973, in the meaning defined above

Time Traveler
The first known use of triathlon was in 1973

Dictionary Entries Near triathlon

Cite this Entry

“Triathlon.” Dictionary, Merriam-Webster, Accessed 28 Mar. 2023.

Kids Definition


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

Last Updated: - Updated example sentences
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