D defs.my
Entry 1 sense Webster, 1913

Siderography

· Sid·er·og·ra·phy · IPA
01 n. The art or practice of steel engraving; especially, the process, invented by Perkins, of multiplying facsimiles of an engraved steel plate …
  1. 1.
    The art or practice of steel engraving; especially, the process, invented by Perkins, of multiplying facsimiles of an engraved steel plate by first rolling over it, when hardened, a soft steel cylinder, and then rolling the cylinder, when hardened, over a soft steel plate, which thus becomes a facsimile of the original. The process has been superseded by electrotypy.