“triathlon” is written with a tilde and without an interspersed “h”
The Urgent Spanish Foundation (Fundéu BBVA) points out that the words “biathlon”, “triathlon”, “pentathlon”, etc., which derive from the Greek “athlos” ('competition' or 'test'), in Latin “athlon” , are written without an interspersed “h” and with an accent.
On June 17, the Copa del World of Triathlon in the Spanish town of Bañolas (Gerona) and in the related information it is possible to find cases in which the name of this test, as well as the name given to its participants, appear written with the etymological transcription that maintains the “h”.
However, in Spanish the suffix “-athlon”, which is part of those words that refer to athletic competitions in which the same athlete must pass different types of tests, is written without an “h”: “biathlon” (two tests) , “triathlon” (three events), “pentathlon” (five events), “heptathlon” (seven events), “decathlon” (ten events).
Likewise, the Fundéu BBVA, which works with the advice of the Royal Spanish Academy, remembers that the athletes who compete in these events are called “biathletes”, “triathletes”, “pentathletes”, “heptathletes” and “decathletes”.
The Urgent Spanish Foundation (www.fundeu.es), promoted by the Efe Agency, sponsored by BBVA and whose main objective is the good use of Spanish in the media, has the collaboration, among others, of Instituto Cervantes, the San Millán Foundation, Spanish Electricity Network, Gómez-Acebo & Pombo, CEDRO, CELER Soluciones, Hermes Traducciones, Linguaserve and Abengoa.
http://www.fundeu.es/