An act, such as a running race or sex, engaged in for a very long time, i.e. at least several hours.

to watch an entire season of a TV series in a short period of time, especially if you watch them in one sitting.

A marathon is when you masturbate numerous times, till one passes out.

A footrace of 42.195 kilometres, which is usually held on roads. It's featured at the Olympics and the World Track and Field Championships. The race was borne out of the death of Greek army messenger Pheidippides, who ran from village of Marathon to Athens to inform the Athenians of the Greek's victory over the Persian army. Pheidippides died upon delivering the message.

YOUR GIRLFRIEND/WIFE AND YOU WILL MAKE LOVE 26.22 TIMES IN ONE NIGHT. THAT’S ROUGHLY 3.3 TIMES PER HOUR, FOR 8-HOURS… THAT WAY, IF YOU GO TO BED AT 10 PM, YOU CAN FINISH AND YET STILL GET ENOUGH SLEEP TO BE PRODUCTIVE THE NEXT-DAY (PREFERABLY A SATURDAY OR SUNDAY). HOORAY! HOWEVER, YOU'RE GOING TO NEED A MINI-FRIDGE, TWO-PLASTIC GLASSES, FOUR-ENERGY DRINKS, SIX-BOTTLED WATERS, THREE-GALLONS OF ORANGE JUICE, 10-MINI BOTTLES OF KY (SUFFICIENT LUBE), AND 2-3 SUB-PAR MOVIES; BECAUSE IF THEY PROVE TOO INTERESTING, YOU AND/OR YOUR LOVER COULD POSSIBLY GET SIDE-TRACKED, COSTING YOU PRECIOUS TIME. THIS TIME SHALL BE CALLED, “MARATHON”.

The greatest game ever.

When you drink 26 beers in a short amount of time, without throwing up.