Swage, n. A tool, variously shaped or grooved on the end or face, used by blacksmiths and other workers in metals, for shaping their work, whether sheet metal or forging, by holding the swage upon the work, or the work upon the swage, and striking with a sledge.
Swage block, a perforated block of iron, having grooved sides and adapted for use in heading bolts and swaging objects of large size.
swage block
n : an iron block cut with holes and grooves to assist in cold
working metal