κέλυφος

Etymology
According to Beekes, connected with the group of, with a suffix.

Noun

 * 1) sheath, case
 * 2)  pod, shell
 * 3)  envelop of a chrysalis
 * 4) eggshell
 * 5)  hollow of the eye

Noun

 * 1) shell
 * 2) eggshell
 * 3) nutshell
 * 4) shell, casing