The Collaborative International Dictionary of English v.0.48:
Nutshell \Nut"shell`\, n.
1. The shell or hard external covering in which the kernel of
a nut is inclosed.
[1913 Webster]
2. Hence, a thing of little compass, or of little value.
[1913 Webster]
3. (Zool.) A shell of the genus Nucula.
[1913 Webster]
in a nutshell in a summarized and very abbreviated form; --
of statments, descriptions, reports, and other
communications; as, to describe the convention in a
nutshell.
To be in a nutshell or To lie in a nutshell,, to be
within a small compass; to admit of very brief or simple
determination or statement. "The remedy lay in a
nutshell." --Macaulay.
[1913 Webster +PJC]