In the ancient Greek story of Pandora, she opened a jar rather than a box.
Hesiod uses the Greek word pithos, which referred to a large earthenware storage jar. Such jars were used in the ancient Mediterranean for commodities including grain, wine, and oil. In Works and Days, Pandora removes the lid of this container, releasing troubles into the world before hope remains inside.
The familiar expression “Pandora’s box” developed much later. Renaissance writers translating or adapting the Greek story helped turn the jar into a box in European languages. The wording became so popular that the modern phrase is now standard, even though it does not describe the container in Hesiod’s original account.
This is one of the best-known translation shifts in classical mythology. Saying “jar” is more faithful to the ancient text, while “Pandora’s box” is the conventional English expression used in later literature and everyday speech.