The ancient Greek vessel identified with Pandora’s container in Hesiod’s original story is a pithos.
A pithos was a large ceramic storage jar used in the ancient Greek world and elsewhere in the eastern Mediterranean. Such vessels could hold agricultural products and were often substantial enough to remain stationary. This makes the traditional image of a small hinged box an important departure from the earliest surviving literary account.
The “box” wording became dominant through later translations and retellings. A Latin translator associated the vessel with pyxis, a word for a box or container, and that choice shaped the expression used in many European languages. The modern phrase is now so established that “Pandora’s jar” can sound unfamiliar even though it is closer to Hesiod.
A kylix was a drinking cup, an amphora commonly had two handles and a narrower neck, and a krater was used for mixing wine and water. None is the vessel named in the Pandora story.