In Ancient Greek this term denotes both moral and non-moral characteristics that were thought to be desirable. Therefore, it has a much broader scope than the English term 'virtue' (which is almost entirely moral in scope). Courage, for example, would be a characteristic Ancient Greeks would have thought necessary to be considered a virtuous (i.e., excellent) person. But the word might also be applied to someone who excelled at their craft (e.g., a virtuous carpenter).
Also see 'Virtue', 'Virtue Ethics', and Aretaic Ethics.