Excellence, merit, virtue, perfection are comparable when meaning a quality or feature of a person or thing that gives him or it especial worth or value.
Excellence applies to a quality or feature in which the person or thing excels or surpasses others; since the term carries no implication of absence of fault, defect, or blemish, it is often qualified (as by particular, specific, or distinctive).
Merit (see also DUE ) may be used interchangeably with excellence, but it typically carries no suggestion of a surpassing quality; rather, it applies to a quality or feature that has evident worth or value or is highly commendable. It is used especially in critical estimates in which good points (merits ) are displayed against bad points (defects or faults).
Virtue, because of the long association of the term with moral goodness (for this sense (see GOODNESS )) is chiefly applied to a moral excellence or a conspicuous merit of character. But the term may also apply to the quality or feature that is the source of a person’s or thing’s peculiar or distinctive strength, power, or efficacy.
Perfection suggests an attainment of the ideal and is usually found in less restrained writing or speech than the other terms when it applies to an excellence in the highest degree.