Pronounced wǎngluòshuǐjūn, it means "internet mercenaries." The term refers to a group of people posting comments online to manipulate public opinion. Some of them, backed by institutions for certain purposes, disguise themselves as ordinary netizens and post comments in order to affect and divert public opinion.
Let's put it into context:
Phil: Hey Allen! I've got a pretty cool part-time job!
Allen: Really? What kind of job is it?
Phil: Well, it's pretty easy. You just stay at home and post comments about certain products online, saying how good the products are and how bad your rivals' are.
Allen: Wow! You'd better be careful. That sounds like you've become a wǎngluòshuǐjūn.
