* ἱκανοποίησις (ikanopóiesis): This is probably the closest single word translation. It implies the fulfillment of a need or desire, a feeling of being content or pleased.
* ἀπόλαυσις (apólausis): This translates to "enjoyment" or "pleasure," and can be used when satisfaction comes from experiencing something pleasurable.
* ἐπιτυχία (epitychía): This means "success" or "achievement," and might be appropriate if the satisfaction stems from accomplishing a goal.
Therefore, the best Greek word for "satisfaction" depends heavily on the context. ἱκανοποίησις (ikanopóiesis) is a good general choice, but consider the others if a more specific meaning is required.