In Greek mythology, Epimetheus’s name was traditionally interpreted to mean “afterthought.”
The interpretation comes from the Greek name Epimetheus and forms a contrast with his brother Prometheus, whose name is traditionally connected with “foresight.” The pair’s names reflect a mythological opposition between acting with advance understanding and recognizing consequences only afterward.
That contrast is especially relevant to Pandora’s story. Prometheus warns Epimetheus not to accept gifts from Zeus, but Epimetheus accepts Pandora anyway. The myth therefore turns the brothers’ names into a compact characterization: Prometheus anticipates danger, while Epimetheus understands it too late.
“Afterthought” is a conventional English gloss rather than a complete translation of every possible nuance of the Greek. It is nevertheless the standard answer in summaries of the myth. Epimetheus should not be confused with Pandora’s container or with the meaning of Pandora’s own name, which is commonly explained as “all-gifted.”