Qin shihuangdi was the first to coin the term "huangdi" which in English is translated as
emperor. The word for "
King" (Wang) was not good enough for him.
The Chinese word (wang) for king represents the levels of Zhou dynasty nobility as horizontal lines, and a single vertical line sweeping through them all. Qinshihuandi took this character, and added another on top of it to form a new one, also pronounced "wang", and combined it with di, the word for a supreme ruler, and gave himself a poetically grand title, first Huangdi, or First Emperor.
It is ironic that he is only known as the First Emperor of Qin, and also the first and last true emperor of his dynasty.