tough egg to crack

and tough nut to crack

n. a person or thing that is hard to figure out or hard to deal with. She won’t talk. She’s going to be a tough nut to crack! I wish Jill wasn’t such a tough nut to crack.

Common Names:

Name	Pronounced	Usage
Zita (2)	-	Hungarian
Sacnite	-	Native American, Mayan
Bran (2)	BRAHN	Welsh, Welsh Mythology
Edda (1)	ED-dah	Italian
Lysander	-	Ancient Greek (Latinized)
Lycus	-	Greek Mythology (Latinized), Ancient Greek (Latinized)