MDBG Mobile Chinese English Dictionary (iPhone, Android, Windows Phone)

膝盖	xī gài	knee / (Internet slang) to kneel down (in admiration)
跪倒	guì dǎo	to kneel down / to sink to one's knees / to grovel
膝	xī	knee
蜷伏	quán fú	to curl up / to lie with knees drawn up / to huddle up
膝下	xī xià	at the knee (in reference to children) / (salutation used in letters to parents or grandparents)
小腿	xiǎo tuǐ	lower leg (from knee to ankle) / shank
发软	fā ruǎn	to weaken / to go soft (at the knees)
卑躬屈膝	bēi gōng qū xī	to bow and bend the knee (idiom); fawning / bending and scraping to curry favor
护膝	hù xī	kneepad / knee brace
下跪	xià guì	to kneel / to go down on one's knees
腘	guó	knee pit / popliteal fossa (medicine)
拜倒	bài dǎo	to prostrate oneself / to fall on one's knees / to grovel
袚	fú	knee-pads / buskins
促膝	cù xī	to sit knee to knee
奴颜婢膝	nú yán bì xī	servile and bending the knee (idiom); fawning / bending and scraping to curry favor
骹	qiāo	shank (the leg from knee to ankle) / leg (from hip to ankle) / (horse anatomy) pastern
长揖	cháng yī	to bow deeply, starting upright with arms straight out in front, one hand cupped in the other, then moving the hands down to one's knees as one bows, keeping the arms straight (a form of greeting)
绕膝	rào xī	(children) run around parent's knees / fig. to stay to look after one's elderly parents
齐膝	qí xī	level with one's knees / knee-length (skirt etc) / knee-deep (mud etc)
腘窝	guó wō	popliteal (anatomy) / hollow at the back of the knee