剑桥词典a device containing a gas in which units of matter smaller than atoms are shown to be present by the small drops of liquid that they produce 云室（一种充满气体的设备，在其内部，比原子小的物质粒子经过时，气体会凝成液滴，液滴的出现证明这种微粒的存在） 返回 cloud chamber