Meaning:

“刷” means to “post something online repeatedly,” “单” means “order,” and “工厂” means “factory.” Chinese netizens use the term to refer to organizations of people who are paid to fake purchases at certain online shops and give positive reviews of their “purchases.” Reports by Chinese media exposed that fake purchases and paid-for high ratings are a “latent rule” used by many online shops on platforms like taobao.com.

Example:

A: 我上周买了件衣服，收到货却大失所望，真不知道怎么会有那么多好评。

Wǒ shàngzhōu mǎi le jiàn yīfú, shōudào huò què dàshīsuǒwàng, zhēn bù zhīdào zěnme huì yǒu nàme duō hǎopíng。

I bought a piece of clothing last week. The purchase was quite disappointing. I don’t get why there were so many good reviews.

B: 店家一定是用刷单工厂了。

Diànjiā yīdìng shì yòng shuādān gōngchǎng le。

The seller must have hired people to post good reviews.