Third person singular present tense of burnish; polishes something to a shine or improves something's reputation or appearance.
From Old French 'brunir' + modern English third person -es. Can be used literally for polishing and metaphorically for improving reputations or situations.
Metaphorically, 'burnishes' became powerful in English—lawyers and publicists 'burnish' their clients' images, and the word gained weight because polishing literally does improve appearance!
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