a Gordian knot

(formal)

a difficult problem

Usage notes: In an old story, King Gordius of Phrygia tied a complicated knot which no one could make loose, until Alexander the Great cut it with his sword.

Homelessness in the inner cities has become a real Gordian knot.

Common Names:

Name	Pronounced	Usage
Alain	al-EN	French
Diodoros	-	Ancient Greek
Norberto	nor-BER-to (Spanish, Italian)	Spanish, Portuguese, Italian
French	[frentʃ]
Dewi (1)	-	Welsh
Jillian	['dʒiliən]