Meaning of -ATHON in English
a suffix extracted from marathon , occurring as the final element in compounds which have the general sense "an event, as a sale or contest, drawn out to unusual length, often until a prearranged goal, as the contribution of a certain amount of money, is reached": walkathon; readathon. Also, -a-thon, -thon .
Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012