There is no "colon" in triathlon. There are three syllables in tri-ath-lon. Make no PHONE calls; use fonetics (don't mail me on phonetics). It's not triathfolon. The sport of swimming, biking and running is the triathlon. Three endurance sports rolled into a three syllable word the "triathlon". Tell your radio and TV sports editors, tell your friends.
Nor is there a colon in duathlon. There are three syllables in du-ath-lon. It's not duathfolon. The sport of running, then biking and then running again is the duathlon. Tell your radio and TV sports editors about the duathlon, tell your friends. Note that the duathlon is often called a biathlon. Many sports people prefer to restrict biathlon to the skiing and shooting sport. However, the biathlon has no large intestine either. Bi-ath-lon, like duathlon, is pronounced with three syllables.
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