Stayer n. One who upholds or supports that which props; one who, or that which, stays, stops, or restrains; also, colloquially, a horse, man, etc., that has endurance, as in a race.
... "I suppose that's the way it goes. Hang it, I guess I was a little too sudden. But I'm a stayer. Maybe you'll change ... — Big Timber - A Story of the Northwest • Bertrand W. Sinclair