A pig-iron is an iron plate suspended between a fire and the meat cooking over it to prevent the meat from burning. This plate acquired the name pig-iron in the mid eighteenth century, but the term itself goes back to the mid seventeenth century when pig-iron referred to an iron ingot—that is, an iron lump—of a particular size, one smaller than a sow-iron. Sow-iron, in fact, is the older term, dating back to the fifteenth century, and may have been bestowed upon the large ingot because its shape and weight, about three hundred pounds, resembled that of a sow.