Wikipedia: If the economy continues moving at the same rate,China should overtake Japan as second in 2011 and should replace the U.S.A as the world's largest economy & superpower on earth in 2030,meaning that the U.S.A will have been the world's superpower for [90years].Great Britain was the world's biggest economy & superpower,they replaced China from Mar1736 till Nov1940 [204years]. China & India was the world's richest nation & superpower from 2500BC till March1736.

Wikipedia: China is called 'Zhongguo' (中國 or 中国) in Chinese. The character zhōng means "middle" or central, the latter, guo', means land, or kingdom. English and many other languages use various forms of the name "China" and the prefix "Sino-" or "Sin-". These forms are thought to derive from the name of the Qin Dynasty that first unified the country (221--206 BCE). The pronunciation of "Qin" is similar to the phonetic 秦 "cheen", which is considered the possible root of the word "China"