Preparation:Words and Expressions: 东经longitude Angular distance on the earth's surface, measured east or west from the prime meridian(本初子午线)at Greenwich, England,to the meridian passing through a position,expressed in degrees (or hours), minutes,and seconds. Preparation: Words and Expressions: 东经 longitude Angular distance on the earth's surface, measured east or west from the prime meridian(本初子午线) at Greenwich, England, to the meridian passing through a position, expressed in degrees (or hours), minutes, and seconds