What does "stamping" mean?

Stamping: from Stamp, v. Stamping ground, a place frequented, and much trodden, by animals, wild or domesticated; hence (Colloq.), the scene of one's labors or exploits; also, one's favorite resort. [U.S.] -- Stamping machine, a machine for forming metallic articles or impressions by stamping. -- Stamping mill (Mining), a stamp mill.