Meaning:
“自” means “self,” and “黑” literally means “black.” Like many English nouns that are used as verbs, the Chinese character “黑” is used here to mean “tainting” or “criticizing.” Therefore, the slang term means “mocking oneself.” With their private life frequently exposed to the public, celebrities are the group of people most easily falling victim to mock and criticism. And many of them have used self mocking as a means to win back the hearts of fans and end disputes. Chinese actress Yang Mi is thought to be an expert of self-mockery. One widespread joke online is that Santa Claus fainted at the strong smell of her stockings when he paid her a visit. The actress joked, “Hi, Santa, are you okay?”
Example:
A: 明星为什么那么喜欢自黑？
Míngxīng wèishénme nàme xǐhuan zìhēi?
Why do all celebrities like to mock themselves?
B: 大概勇于自黑其实是表现了自信，同时也拉近了和粉丝的距离。
Dàigài yǒngyú zìhēi qíshí shì biǎoxiàn le zìxìn, tóngshí yě lājìn le hé fěnsī de jùlí。
Perhaps self-mockery in fact reveals their confidence and it also makes them appear less standoffish.
(Edited by Stephanie Yang)