In the original Greek version of Pandora’s myth, Pandora opened a pithos, a large storage jar.
The Greek word pithos referred to a substantial earthenware container used for storing goods such as grain, oil, or wine. Hesiod’s Works and Days uses this word rather than a word meaning a small hinged box. The famous English title “Pandora’s box” therefore does not precisely reproduce the ancient object.
The change is generally associated with later translation and retelling traditions. Erasmus’s Latin rendering helped popularize the idea of a box, and that image became dominant in European culture. Modern artistic depictions consequently tend to show Pandora lifting a lid from a small chest.
A pithos was not merely decorative: large examples could be taller than a person and were important household storage vessels in the ancient Mediterranean. “Jar” is the safest ordinary-English description, while pithos is the specific ancient Greek term.