a hard nut to crack
a difficult problem to solve

[TahlilGaran] Dictionary of Contemporary English ▲

hard nut to crack
a difficult problem to solve.
A company whose product has sold well in the States may find the European market a tougher nut to crack.

a tough 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.

a tough 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.

[TahlilGaran] English Idioms Dictionary ▲

hard nut to crack
a difficult person or thing to deal with
My friend is a very serious person and she is a very hard nut to crack.

[TahlilGaran] English Idioms Dictionary ▲

hard nut to crack
n. phr., informal Something difficult to understand or to do.
Tom's algebra lesson was a hard nut to crack.
Mary found knitting a hard nut to crack.
Compare: HARD ROW TO HOE.

[TahlilGaran] English Idioms Dictionary ▲