Intestinal fortitude is defined as courage and endurance to go on.

bottle [British slang], bravery, courage, courageousness, daring, daringness, dauntlessness, doughtiness, fearlessness, gallantry, greatheartedness, GUTS, gutsiness, hardihood, heart, heroism, intrepidity, intrepidness, moxie, nerve, stoutness, valor, virtue

Tell the world that you've got Intestinal Fortitude while you rep your new favorite brand!