Epicurus Syllabification: (Ep·i·cu·rus)Pronunciation: /ˌepəˈkyo͝orəs/Definition of Epicurus (341–270 bc), Greek philosopher, founder of Epicureanism. His physics is based on Democritus' theory of a materialist universe composed of indestructible atoms moving in a void, unregulated by divine providence. Epicurus in other Oxford dictionaries Definition of Epicurus in the British & World English dictionary