By degrees; gradually, step by step.
Latin adverb form meaning 'step by step', directly from 'gradus' (step) with the -tim suffix creating an adverbial form. Rarely used in modern English except in specialized academic or musical contexts.
Medieval scholars wrote 'gradatim' in their margins to mean 'go slowly'—it's a tiny word that captures the entire philosophy of the Middle Ages, where rushing was considered both foolish and unchristian.
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