Pandora’s jar is called a pithos in the original Greek of Hesiod’s Works and Days.
A pithos was a large Greek storage jar, commonly used for commodities such as grain, oil, or wine. Hesiod’s choice of word describes a substantial household container rather than a small hinged box. The jar’s scale fits the poem’s image of troubles being held inside until Pandora opens it.
The phrase “Pandora’s box” became standard much later through translation and artistic tradition. The Latin writer Erasmus helped popularize the box wording in the sixteenth century, and it became the familiar expression in many modern languages.
An amphora is also a Greek vessel, but it is a different form, usually taller and narrower with two handles. A krater was used for mixing wine and water, while a kylix was a drinking cup. None is Hesiod’s pithos.