In Greek mythology, Pandora’s container was traditionally called a jar.
The oldest surviving accounts, by the Greek poet Hesiod, describe a large storage jar rather than a wooden box. The Greek word pithos referred to a substantial earthenware vessel used for storing goods such as grain, wine, or oil. Pandora opened this vessel, releasing troubles into the human world while hope remained inside.
The familiar phrase “Pandora’s box” arose much later through translation history. The Renaissance humanist Erasmus rendered the Greek vessel as a Latin pyxis, meaning a small box or container, in a 1508 edition of Hesiod. That wording helped establish the expression used in English and many other languages.
The myth is therefore often illustrated with a box, even though the earliest version specifies a jar. The container’s shape is a translation issue, not a separate version of the story. “Pandora’s box” remains the standard modern expression for an action that creates many unforeseen problems.