卖萌 (mài méng) acting cute; playing cute

Usage:

“萌”的意思是可爱，“卖萌”就是刻意做出一些可爱的动作、言语等，是个中性词。
“萌” means cute, and “卖萌” is to be deliberately cutesy in action or speech. It carries a neutral connotation.
Sentences:

1、Nǐ dōu duō dà le, hái xǐhuan màiméng.
你都多大了，还喜欢卖萌。
Why you still deliberately act cute at such a mature age!

2、Kàn zhè zhī xiǎo māo zài màiméng, duō kě’ ài a!
看这只小猫在卖萌，多可爱啊！
Look at that kitten playing cute. How adorable!