In Hesiod’s account of Pandora, the vessel Zeus gave her was a pithos.
A pithos was a large ancient Greek storage jar, commonly used for commodities such as grain, wine, or oil. Hesiod’s Greek wording describes a pithos rather than the small domestic box suggested by the familiar English phrase “Pandora’s box.”
The container became a box through a later translation tradition. The Renaissance humanist Erasmus of Rotterdam used the Latin word pyxis, meaning a small box or casket, in his influential retelling. That choice helped establish the expression now used in English and many other languages.
The vessel’s exact contents also vary in later retellings. Hesiod describes destructive troubles escaping into the human world, while hope remains inside. The jar’s scale and function are therefore important clues to the earliest surviving version of the story.