"move or run by leaps," early 15c., from Old French galoper "to gallop" (12c.), central Old French form of Old North French waloper, probably from Frankish *wala hlaupan "to run well" (see wallop). Related: Galloped; galloping. Though the French word is Germanic, Dutch galopperen, German galoppiren, Swedish galoppera are from French.
"a leaping gait," the most rapid movement of a horse, 1520s, from gallop (v.).