hourglass

◊ An hourglass is a glass container with an upper part and a lower part connected by a narrow opening. The upper part contains sand which flows into the lower part in a specified amount of time (such as an hour).沙漏（一种玻璃容器，分为上下两部分，中间由一个细口连接。装在上部的沙子会在一定的时间，比如一个小时内全部漏入下部。）