Greek ἡδονή (hēdonē); Latin voluptas
Pleasure, which Epicurus called "the beginning and end of the blessed life." Pleasure is the standard by which every choice and avoidance is judged, and it includes every experience that is not painful, of body and of mind alike. See Pleasure Is the Guide and The Term "Pleasure" Is The Exact Equivalent Of "Absence of Pain".
1. Key Texts
Quote from Epicurus, Letter to Menoeceus 128-9 (Pleasure as the Standard by Which We Judge Every Good)We recognize pleasure as the first good innate in us, and from pleasure we begin every act of choice and avoidance, and to pleasure we return again, using the feeling as the standard by which we judge every good. And since pleasure is the first good and natural to us, for this reason we do not choose every pleasure whatsoever, but sometimes we pass over many pleasures when a greater annoyance ensues from them; and similarly we think many pains better than pleasures when submission to the pains for a long time brings us as a consequence a greater pleasure. (Bailey)