Gordian knot (n.)youdaoicibaDictYouDict[Gordian knot 词源字典]
1560s, tied by Gordius (Greek Gordios), first king of Phrygia in Asia Minor and father of Midas, who predicted the one to loosen it would rule Asia. Instead, Alexander the Great cut the Gordian knot with his sword; hence the extended sense (1570s in English) "solve a difficult problem in a quick, dramatic way."[Gordian knot etymology, Gordian knot origin, 英语词源]