Meaning

noun any long and arduous undertaking

noun a footrace of 26 miles 385 yards

noun a battle in 490 BC in which the Athenians and their allies defeated the Persians

originFrom French marathon, coined in 1894 by linguist Michel Bréal for the first modern time Olympic Games after Ancient Greek Μαραθών (Marathṓn), a town northeast of Athens. Phidippides the Greek ran the distance from Marathon to Athens to deliver a message regarding the Battle of Marathon. The modern sport of marathon running is based on a run approximately the same distance. The toponym itself…

Etymology from Wiktionary, CC BY-SA 3.0