The standard English phrase for the myth of Pandora’s opened jar is “Pandora’s box.” The expression refers to the story in which Pandora opens a container and releases troubles into the human world, with Hope remaining inside according to the conventional modern retelling.
This phrase is historically notable because the earliest surviving Greek version does not describe a box. Hesiod uses the word pithos, meaning a large storage jar. The English “box” became dominant through later translation and cultural adaptation, and it is now so established that it usually names both the object and the myth itself.
In modern English, opening Pandora’s box also functions as an idiom. It means starting a chain of complicated or harmful consequences that are difficult to reverse. The idiom can describe politics, technology, science, or personal decisions, even when no mythological subject is intended. Its meaning depends on the myth’s central image of troubles escaping once the container is opened.