From La Cuisine Creole by Lafcadio Hearn (circa 1885): A nappy is a round, shallow pottery bowl with a flat bottom and sloping sides. They are the most commonly found of yellow and white ware. The word nappy comes from the Middle English word "nap" meaning bowl. Some nappies were large enough for several quarts of milk. They ranged from 3 to 12 inches in diameter.
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