Amarillo (ămərĭl`ō, –`ə), city (1990 pop. 157,615), seat of Potter co., N Tex.; inc. 1899. The commercial and industrial center of the Texas Panhandle, Amarillo grew after the coming of the railroad in 1887, becoming a market for wheat farmers. After the discovery of gas (1918) and oil (1921), Amarillo developed into an industrial city. Its economy is also based on ranching, meatpacking, flour milling, zinc and copper smelting, and the manufacture of helicopters, wood and fiberglass products, synthetic rubber, and cattle feed. A U.S. government helium plant and the Federal Helium Preserve are nearby; the Pantex plant, east of the city, which formerly built nuclear weapons, now disassembles them.