What is to cover with a ground, as a copper plate for etching (see Ground, n., 5); or as paper or other materials with a uniform tint as a preparation for ornament called?

ground — (Fine Arts) To cover with a ground, as a copper plate for etching (see Ground, n., 5); or as paper or other materials with a uniform tint as a preparation for ornament. (Webster's 1913.)

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