Eudaimonia is a horrible word - it has a moan in the middle, for one thing - and, to make matters even worse, it's a word which means something beautiful.
The idea was made up by Aristotle, so it's been around usefully for a long time.
Eudaimonia means...well, it means eudaimonia, but people have translated the word as happiness, or well-being, or flourishing. It's the process of living your life so that you can give expression to the very best parts of yourself, the parts which make you and the world both better and happy.
But, sadly, the word is still a mixture of eu, demons, and moans.
And so I can't recommend it.
Sunday Rest: eudaimonia. The eu bit means good, and the daimon bit means spirit. In Greek, obviously.
The same idea is present in the daemons of Philip Pullman's His Dark Materials novels.