(Gr. ido-rn, Lat. cista, a box; cf. Ger. Kiste, Welsh kistvaen, stone-coffin, and also the other Eng. form "chest"), in Greek archaeology, a wicker-work receptacle used in the Eleusinian and other mysteries to carry the sacred vessels; also, in the archaeology of prehistoric man, a coffin formed of flat stones placed edgeways with another flat stone for a cover. The word is also used for a sepulchral chamber cut in the rock (see Coffin).
"Cistern," the common term for a water-tank, is a derivation of the same word (Lat. cisterna; cf. "cave" and "cavern") .