Word Definition - 卧薪尝胆

wò xīn cháng dǎn lit. to sleep on brushwood and taste gall (like King Goujian of Yue 勾踐|勾践[gōu jiàn], in order to recall one's humiliations) (idiom); fig. to maintain one's resolve for revenge; variant of 臥薪嘗膽|卧薪尝胆[wò xīn cháng dǎn]