What is the Greek word for feeling good?

There isn't one single perfect Greek word to translate the English phrase "feeling good," as the best choice depends on the nuance you want to convey. However, here are a few options with slightly different connotations:

* Ευδιαθεσία (eudiathesia): This is probably the closest single word. It refers to a general feeling of well-being, good mood, and pleasant disposition.

* Ευχαρίστηση (eucharístēsi): This means "pleasure" or "delight," and implies a feeling of satisfaction or enjoyment. It's suitable if the "feeling good" is linked to a specific cause.

* Αρετή (aretē): While usually translated as "virtue" or "excellence," in a broader sense it can also refer to a state of flourishing and well-being, feeling good about oneself and one's life. This is a more philosophical and less immediate feeling than the others.

The best word to use will depend on the context. If you can provide the context, a more precise translation can be offered.