nutshell

The shell enclosing the meat of a nut.

(in a nutshell) In a few words; concisely.

The hard shell which forms the covering of the kernel of a nut: used proverbially for anything of small content or of little value.

A bivalve mollusk of the family Nuculidæ; a nutlet.

The shell or hard external covering in which the kernel of a nut is inclosed.

Hence, a thing of little compass, or of little value.

A shell of the genus Nucula.

in a summarized and very abbreviated form; — of statments, descriptions, reports, and other communications.

to be within a small compass; to admit of very brief or simple determination or statement.