“拼” here means to “put together,” as in “put together a jigsaw puzzle,” and “团” is short for “团购” (tuángòu), which means “group buying.” Therefore, this term, coined by Chinese netizens, refers to the scenario where people join a group buying effort so that each can enjoy a lower price than when they buy individually. Such group buying activities often occur online, via social media and shopping sites.
Lái chángchang wǒ mǎi de píngguǒ。
Come over and try the apples I bought.
Zhēn xīnxiān，nǎlǐ mǎi de？
They look so fresh. Where did you buy them?
Wǒmen gōngsī yǒu tóngshì zǔzhī de tuángòu，cóng yúnnán zhíjiē yùn guòlái de。
Someone in my company put together a group buying effort, and the apples were sent directly from Yunnan Province.
Xiàcì pīntuán yě jiào shàng wǒ。
Count me in the next time you have a group-buy.