There isn't a scientific definition for this sort of concept, though I would generally translate it to mean 'Personality' and in a similar vein 'Spirit' tends to translate as 'Emotion'.
Quote:I don't understand why you'd come to a discussion forum, and then proceed to reap from visibility any voice that disagrees with you. If you're going to do that, why not just sit in front of a mirror and pat yourself on the back continuously?-Esquilax
Evolution - Adapt or be eaten.