In the original Greek version of Pandora’s myth, Pandora opened a jar. Hesiod used the Greek word pithos, which referred to a large storage jar commonly used for grain, wine, or other goods.
The familiar expression “Pandora’s box” developed much later. In the 16th century, the humanist Desiderius Erasmus translated the Greek vessel using a Latin word associated with a small container or box. That translation helped establish the wording now used in English and many other languages.
This is one of the best-known differences between the ancient story and its modern name. The change from jar to box does not alter the central idea: once the container was opened, troubles escaped into the world. Artistic depictions frequently show a hinged box because that is what modern audiences expect from the phrase.
The jar detail matters because it links the myth to ordinary ancient household storage rather than to a special magical chest.