I love etymology. Not enough to be a philologist, but enough to be dangerous. Half the problems with words is determining intent, i.e. how the word was used.
Truth is, most words have more than one meaning and even certain types of words, say nouns, frequently get modified into verbs or gerundives.
With Ancient Greek it gets real tricky since one word can have hundreds of meanings. Take logos for example. It can mean word or book or Scripture or letter or...well you get the point.
So I'm googling some stuff around mood and the like and I see it ultimately comes from a Greek word, orge, which means anger. I then start to wonder if it's also the root of orgy. It turn out that orgy is associated with ergo, meaning to work, i.e. to work into a state of frenzy. Originally, it meant a singing and dancing festival for the gods that was fairly revelrous. But the o at the beginning of the word...
What I figure is that orgy was a combination of ergo, to work, and orge, full of mood possibly strongly and you literally have 'work up a mood.' Neat.
