IPA: //ˈbaɪ.æθ.lɒn//
KK: /ˈbaɪ.æθ.lɒn/
A sport that involves two activities: skiing over a long distance and shooting at targets with a rifle.
She trained hard for the biathlon, balancing her time between skiing and shooting practice.
Biathlon → It is formed from "bi-" (meaning two) and "athlon" (from Greek "athlon", meaning contest or prize). The word refers to a contest involving two different sports, typically skiing and shooting.
Think of 'two' ('bi-') sports competing in a 'contest' ('athlon') — that's what a biathlon is.