The act itself is familiar to anyone who's ever watched comedy: One character takes a swig or bite of something just as another character says or does something shocking¹ or outrageous², causing the first character to spew out the contents of his or her mouth. It's called a spit take. 

看过喜剧的人对这样的场景不会陌生：剧中一位人物正在喝东西，另一位人物做了一些让人吃惊或者觉得离谱的事情，正在喝东西的人当场把嘴里的饮品喷出来，这就是“笑喷”。

 

Spit take is an act of suddenly spitting out liquid one is drinking in response to something funny or surprising: 

“笑喷”指的是在听到或看到一些有趣或惊讶的事情时，口中突然喷出正在喝的饮品。