Reduced to or covered with powder, which is a fine dry substance made of tiny particles.
From Old French 'poudre,' derived from Latin 'pulvis' (dust). The word entered English in the 13th century and has meant both the substance itself and things coated with it.
Powdered sugar was invented as a way to preserve sugar in humid climates—finely powdering it reduced moisture absorption, so the cooking technique actually solved a real storage problem!
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