The Greek vessel in Pandora’s myth was a pithos, a large storage jar.
In Hesiod’s Works and Days, Pandora receives a container holding the evils that later escape into the world. The Greek word pithos refers to a substantial earthenware jar commonly used for storing goods such as grain, oil, or wine. It was not specifically a small box designed for personal possessions.
The familiar expression “Pandora’s box” developed through a translation tradition. The Renaissance scholar Erasmus rendered the container with the Latin word pyxis, meaning a box or small container, rather than preserving the original pithos. That choice helped establish the wording used in many modern languages.
Archaeological pithoi could be very large, sometimes standing taller than a person. This is why “Pandora’s jar” is a more literal description of the ancient Greek version, while “Pandora’s box” is the standard later phrase.