独 (dú) by oneself; alone; single; independent; sole

金鸡独立 : jīn jī dù lì (спорт. петушиная стойка на одной ноге (приём в кит. борьбе) 独树一帜 (dú shù yí zhì) idiom. to set up a separate flag -- fly one's own colours, become an independent school, have a style of one's own