Elpis is the Greek name of the spirit that remained inside Pandora’s container in Hesiod’s Works and Days.
Elpis is commonly translated as “hope,” though the exact meaning and role of the word have been debated. After Pandora opens the container, harmful conditions escape, but Elpis remains inside. The poem says this happens because Pandora replaces the lid before Elpis can leave.
The detail is more complicated than the popular phrase “hope was left behind.” Some interpretations see hope as a benefit preserved for humanity; others ask why hope would be confined with the evils. Ancient Greek ideas about elpis could include expectation of future events, not only modern emotional optimism.
The name Elpis also appears elsewhere in Greek tradition as a personification. In the Pandora story, however, it is specifically the final entity associated with the container. “Hope” is the usual English translation, but Elpis is the precise Greek name.