Greek ἀλγηδών (algēdōn), also πόνος (ponos); Latin dolor
Pain, the only thing bad in itself, as pleasure is the only thing good in itself. Epicurus taught that intense pain is brief and long-lasting pain is mild, so pain need not be feared.
1. Key Texts
Quote from Epicurus, Principal Doctrine 4Pain does not last continuously in the flesh: when acute it is there for a very short time, while the pain which just exceeds the pleasure in the flesh does not persist for many days; and chronic illnesses contain an excess of pleasure in the flesh over pain. (tr. Long & Sedley)