To sink the fish and birds
An extraordinarily beautiful woman
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张小姐长得沉鱼落雁，难怪追求她的人大排长龙! | Zhāng Xiǎojiě zhǎng dé chényúluòyàn, nánguài zhuīqiú tā de rén dàpáichánglóng!
Miss Zhang is devastatingly gorgeous, so it's no wonder that there's a long line of people pursuing her!
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久闻她美艳动人，今日一见，果真是沉鱼落雁之貌 | Jiǔ wén tā měiyàn dòngrén, jīnrì yī jiàn, guǒzhēn shì chényúluòyàn zhī mào
I've long heard that she's drop-dead gorgeous. Today I saw her, and she really is beautiful enough to make fish sink and birds fall
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落雁沉鱼 (luò yàn chén yú)
沈鱼落雁 (chén yú luò yàn)
I'm not sure why some English dictionaries suggest that "落雁" (luò yàn) means the bird is starting to fly. 落 means to sink/fall, and the stories further make it clear that the bird fell from mid-air.
《庄子》(Zhuāng Zǐ), a work written by 庄子 (Zhuāng Zǐ, the same as in the title) during the Warring States Period (475 - 221 BC)
Under construction - the story is accurate, but it will be wordsmithed
Throughout the history of China, there have been four women legendary for being beautiful enough to bring entire countries to their knees. One of these women, 西施 (Xī Shì), was a concubine gifted to the king of 吴国 (Wú Guó) by the king of 越国 (Yuè Guó). It is said that one day, when 西施 was washing silk by the river in her hometown, a fish saw her beauty and felt so ashamed by its own ugliness that it sank to the riverbed, not daring to approach the surface again.
A second beauty lived during the Hàn Dynasty (汉, 206 BC - 220 AD). 王昭君 (Wáng Zhāojūn) was part of the imperial court, and she was brought to marry the leader of the 匈奴 tribe. The day she arrived, an goose flying high in the sky was so astonished by her beauty that it forgot to fly and dropped into the forest below