In Hesiod’s original Greek myth, Pandora opened a pithos, a large storage vessel.
The pithos was a substantial earthenware jar used in the ancient Greek world for storing goods such as grain, oil, or wine. Hesiod’s Works and Days uses the Greek word pithos when describing the container associated with Pandora. It was not a small hinged box in the modern sense.
The phrase “Pandora’s box” became standard after the Renaissance. The Latin writer Erasmus translated or rendered the vessel as a box, using the Latin pyxis, and that wording influenced later European languages and popular culture. Artists subsequently made the box-shaped version familiar.
This translation history explains why the title of the myth can be misleading. Both “Pandora’s pithos” and “Pandora’s box” refer to the same narrative object, but the ancient vessel was closer to a large jar. The Greek term is therefore the most precise answer for the original myth.