Pictogram (象形), resembling a window. Variant characters: 冏, 臦, 臩.
The slang sense is an emoticon used to express helplessness or awkwardness, usually in a humourous way. This usage gained popularity on Taiwanese forums (aka "BBS"), then spread through the media to Hong Kong, and eventually to Mainland China. Its meaning was influenced by the character 窘 (jiǒng, “hard-pressed; embarrassed”) (homophonic in Mandarin).
Ér nàxiē shēnghuó zài guānghuán zhōng de míngxīng hé míngrén men, céngjīng yě yǒu guò lèisì de jīnglì, tāmen nánwàng de wǎngshì zhōng yě bùfá qùwén hé jiǒng shì...... Lǐ Xiǎng zài gāosān shí xuǎnzé fàngqì gāokǎo, què chénggōng chuàngyè, shēnjià shàng yì.[Pinyin]
The celebrities and notabilities now living under spotlights used to have similar experiences; there was no lack of amusing anecdotes and embarrassing moments in their unforgettable pasts ... Li Xiang dropped out of school during the third year of high school, choosing not to take the University Entrance Examination. Instead, he successfully started an enterprise, now worth hundreds of millions.