n.坚果壳;小容器;简明扼要
The nutshell includes the kernel. 果壳裹着果仁。
He put the situation in a nutshell. 他简明扼要地说明了情况。
The new system is very complicated, but I will try to explain it in a nutshell. 新方法是很复杂的,但我要设法简明扼要地解释一下。