[ trahy-ath-luhn ]
/ traɪˈæθ lən /
Save This Word!

an athletic contest comprising three consecutive events, usually swimming, bicycling, and distance running.
a women's track-and-field competition comprising the 100-meter dash, high jump, and shot put.
British. a competition comprising fly-casting, horseback-riding, and trapshooting events.
Hold your head up high as you embark on this quiz that explores some of the synonyms and meanings of “pride.”
Question 1 of 7
What does "dignity" mean?

Origin of triathlon

First recorded in 1970–75; tri- + (dec)athlon
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022


What is a triathlon?

The word triathlon most commonly refers to an athletic competition in which athletes compete in a race that involves swimming, cycling, and distance running.

The traditional triathlon begins with a 1.5-kilometer open-water swim, followed by a 40-kilometer bike race, and finishes with a 10-kilometer run. This triathlon format is an event in the Summer Olympic Games.

Triathlons sometimes feature different formats. A longer version often branded as an Ironman triathlon consists of a 2.4-mile (3.9-km) swim, a 112-mile (180.2-km) bike, and marathon-length run of 26.2 miles (42.2 km).

In 2021, the Olympics introduced a shorter, relay version of the triathlon featuring teams of two men and two women. Each member of the team must complete a triathlon consisting of a 300-meter swim, an 8-kilometer bike ride, and a 2-kilometer run.

The name triathlon is also applied to other three-part athletic competitions that are not a race but are instead score-based (the three events are not held directly one after another as part of a race like they are in the swim-cycle-run version of a triathlon).

The track-and-field version of a triathlon consists of the 100-meter dash, high jump, and shot put.

In the U.K., the word triathlon sometimes refers to a three-part skill competition involving fly-casting, horseback-riding, and trapshooting.

A triathlon is sometimes informally called a tri for short. Athletes who participate in a triathlon can be called triathletes.

Example: The triathlon is nearing its third stage now as the triathletes transition from the cycling portion to the run.

Where does triathlon come from?

The first record of the word triathlon comes from the 1970s. It’s modeled on the word decathlon, which refers to a 10-part athletic competition. It uses the Greek root âthlon, which means “prize” or “contest” and is also the basis of the words athlete and athletics. Instead of the prefix dec-, meaning “ten,” triathlon uses the prefix tri-, meaning “three.” The names of other multipart athletic competitions are formed in the same way, including biathlon (two events), pentathlon (five events), and heptathlon (seven events).

Races involving a combination of swimming, cycling, and running began gaining popularity in the 1970s. The swim-cycle-run version of the triathlon was first adopted as an Olympic event at the 2000 Summer Olympics in Sydney, Australia.

Did you know … ?

What are some other forms related to triathlon?

What are some words that share a root or word element with triathlon

What are some words that often get used in discussing triathlon?

How is triathlon used in real life?

The most common version of a triathlon involves a 1.5-km open-water swim, a 40-km bike, and a 10-km run, but triathlon formats vary. Triathletes are known for their endurance.

Try using triathlon!

Which of the following events is NOT part of the Olympic triathlon?

A. swimming
B. horseback riding
C. cycling
D. running

How to use triathlon in a sentence

British Dictionary definitions for triathlon

/ (traɪˈæθlɒn) /

an athletic contest in which each athlete competes in three different events: swimming, cycling, and running

Derived forms of triathlon

triathlete, noun

Word Origin for triathlon

C20: from tri- + Greek athlon contest
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012