eu·dae·mo·nia \ˌyüdēˈmōnēə\noun alsoeu·dai·mo·nia\-ˌdīˈ-, -(ˌ)dāˈ-\ (-s) Etymology: Greek eudaimonia, from eudaimon-, eudaimōn having a good attendant or indwelling spirit, lucky, happy (from eu- + daimon-, daimōn spirit) + -ia -y — more at demon 1.: well-being, happiness 2.Aristotelianism: a life of activity governed by reason