The ancient Greek container in Pandora’s story was a pithos, a large storage jar, rather than a box. Hesiod uses the Greek word pithos when describing the vessel associated with the release of evils.
A pithos was a substantial earthenware container used in the ancient Mediterranean for storing commodities such as grain, oil, or wine. Its size and shape differ from the compact wooden or metal box shown in many modern illustrations of Pandora.
The familiar English phrase “Pandora’s box” arose later. In the sixteenth century, the humanist Erasmus translated the Greek vessel as a box in Latin, helping establish the wording that became standard in European languages. Artists, writers, and popular culture then reinforced that image.
This does not make “Pandora’s box” an incorrect modern expression; it is the established idiom. The distinction matters when identifying what the earliest surviving Greek account actually says. The jar is part of Hesiod’s Works and Days, not a later invention.