IPA: /ˈmærəˌθɒn/
KK: /ˈmɛr əˌθɒn/
A long-distance race that is usually 26 miles and 385 yards, or an event that requires a lot of effort and endurance.
She trained for months to prepare for the marathon.
Marathon → The word originates from the name of the plain of Marathon in Greece, where the Battle of Marathon took place in 490 BC. The term is derived from the legend of Pheidippides, a Greek messenger who ran from Marathon to Athens to announce the victory over the Persians, thus giving rise to the modern long-distance running event.
Imagine a messenger running a long distance from Marathon to Athens to deliver important news — that's how the word marathon came to represent a long-distance race.