In Greek mythology, Pandora opened a jar rather than a box.
Hesiod’s Works and Days uses the ancient Greek word pithos, which generally referred to a large storage jar used for commodities such as grain, oil, or wine. The familiar phrase “Pandora’s box” developed later through translation and artistic tradition rather than reflecting Hesiod’s exact wording.
The difference matters because the vessel was substantial and practical in the ancient Greek world, not necessarily a small decorative container. Erasmus helped popularize the Latin form pyxis, meaning a box or small container, and that wording influenced later European retellings. The modern phrase now means an action that releases many unforeseen troubles.