Yours, Etc.: Origins and Uses of 8 Sign-Offs
1751, with reference to a philosophy; 1847 in a general sense, from epicurean + -ism. Earlier was epicurism (1570s).
A form of hedonism defended by several philosophers of ancient Greece. For the Epicureans, the proper goal of action was pleasure — a long-term pleasure, marked by serenity and temperance.