n. Performance; accomplishment.n. The state of being perfect, as in material, form, design, composition, construction, operation, action, qualification, etc.; that degree of excellence which leaves nothing to be desired, or in which nothing requisite is wanting; entire freedom from defect, blemish, weakness, or liability to err or fail; supreme excellence, whether moral or material; completeness or thoroughness: as, perfection in an art; fruits in perfection; the perfection of beauty: often used concretely: as, she is perfection.n. A quality, trait, feature, endowment, or acquirement that is characterized by excellence or is of great worth or value; excellency.n. The extreme; the highest degree; consummation: as, the perfection of cruelty.n. In medieval music, triple rhythm or measure. See measuren. With the highest degree of excellence or success: as, he acted the part to perfection.n. Synonyms Perfectness, completion, consummation.To complete; make perfect.