The Greek word describing the jar in Hesiod’s Pandora story is pithos.
A pithos was a large storage vessel used in the ancient Greek world, commonly for commodities such as grain, oil, or wine. In Works and Days, Hesiod uses the word pithos for the container given to Pandora. It was not a small jewelry box or a modern hinged box.
The familiar phrase “Pandora’s box” developed through later translation history. The Latin writer Erasmus helped popularize the box wording when he rendered the Greek vessel as pyxis, a term associated with a box. Once that version became influential, “Pandora’s box” became the standard expression in English and many other languages.
Pithos is therefore the precise ancient term, while “jar” is a clear English translation. Amphora, krater, and kylix are also Greek vessel names, but they refer to different container types and are not the word used for Pandora’s container.