The ruler of a country is the person who rules the country.
例句
...the former military ruler of Lesotho...萊索托的前軍事統(tǒng)治者He was a weak-willed and indecisive ruler.他是一位意志薄弱、優(yōu)柔寡斷的統(tǒng)治者。
N-COUNT
尺;直尺
A ruler is a long flat piece of wood, metal, or plastic with straight edges marked in centimetres or inches. Rulers are used to measure things and to draw straight lines.