Meaning:
“开口” means to “open one’s mouth,” and “崩” means to “collapse.” This phrase coined by netizens is the short form of “一开口形象就崩溃” (A person’s good image is destroyed the moment he or she speaks). Some netizens have jokingly used a gif of a groundhog suddenly baring its teeth to illustrate the idea.
Example:
A: 小李的女朋友你认识吗？真漂亮啊！
Xiǎolǐ de nǚpéngyǒu nǐ rènshí ma? Zhēn
piàoliang a!
Do you know Xiaoli’s girlfriend? She’s gorgeous!
B: 她是长得美，但没读过什么书，所以开口崩。
Tā shì zhǎng de měi, dàn méi dú guò shénme shū, suǒyǐ kāikǒubēng。
She is pretty. But not well-educated, she loses her glamour the moment she speaks.
(Edited by Stephanie Yang)