An archaic or obsolete word meaning to sweeten or make pleasant; to soften in manner.
From Old French adulcir, from Latin adulcis or adducis, possibly related to dulcis (sweet). The word is rarely used in modern English and appears mainly in historical texts.
Adulce is a ghost word in English—it barely survives except in old dictionaries, showing how languages constantly lose words when they're not useful enough to keep speaking them.
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