Why this word is great
FELLRUNNING — [Noun] The act of running across steep, open terrain, particularly the fells of northern England, as a sport or pursuit. From fell (Old Norse *fjall*, "hill, mountain") + running (Old English *rinnan*, "to flow, to move swiftly"), it is the art of moving fluidly over land that resists fluidity. Unlike "trail running" (which follows groomed paths) or "mountain running" (which may stick to ridges or valleys), fellrunning demands a surrender to the land’s raw contours—no trail, only intuition. It is the scrape of boots on scree, the sudden give of peat underfoot, the way a runner becomes indistinguishable from the slope itself, a fleeting shadow racing the weather. To run the fells is to know the earth as both adversary and accomplice.