crater
noun [ C ] uk/ˈkreɪ.tər/ us/ˈkreɪ.t̬ɚ/
火山口;（火山口似的）坑
the round hole at the top of a volcano, or a hole in the ground similar to this
the huge crater of Vesuvius 巨大的维苏威火山口
a bomb crater 炸弹坑
With a good telescope, you can see craters on the moon. 用好的望远镜能看到月亮上的环形山。