That which may be reduced to fine powder. From Latin pulvis, pulveris, powder. Pulverous, consisting of, or like, dust or powder.--Daniel Lyons's Dictionary of the English Language, 1897
Feast Day of St. Cosmas,
a patron of apothecaries, whose ranks in England included grocers and even purveyors of preserves and "non-perishable commodities" until 1617. Martha Bradley's The British Housewife, or The Cook, Housekeeper's, and Gardener's Companion (1756) described a commonly employed technique for making such medicines as "a powder for convulsive fits," whose sole ingredient was a plucked raven: "Pick off the feathers, gut it, and send it to the oven in a clean earthen dish. Let it be put in every time the oven is heated till it will rub to a fine powder. Of this powder, let the person afflicted take as much as will lie upon a silver groat every morning fasting, for nine days together. This is very seldom known to fail of giving relief, but as it is a disorder that often returns, it will be very proper to keep some of the powder always in the readiness."