pile down

• n. 反应堆的逐渐停堆

pile down的用法和样例：

例句

用作名词 (n.)

1. But as the universe cooled down and thinned out, the collisions became less violent, and the process ground to a halt.
   但是当宇宙冷却且变得稀薄后，上述过程便逐渐停下来。