a tough nut

a tough nut (to crack)

also a hard nut (to crack)

a difficult problem to solve Unemployment is a tough nut. Overcoming local trade barriers is going to be a hard nut to crack.

Name	Pronounced	Usage
Adrianna	ayd-ree-AN-ə (English), ahd-RYAHN-nah (Polish)	English, Polish
Dana (3)	-	Bulgarian, Macedonian
Deon	-	English, African American
Ruaraidh	-	Scottish
Hallie	HAL-ee	English
Thacker	['θækə]