What does "etch" mean?

Etch: To produce, as figures or designs, on mental, glass, or the like, by means of lines or strokes eaten in or corroded by means of some strong acid. Note: The plate is first covered with varnish, or some other ground capable of resisting the acid, and this is then scored or scratched with a needle, or similar instrument, so as to form the drawing; the plate is then covered with acid, which corrodes the metal in the lines thus laid bare.

Additional senses

  1. 2.To subject to etching; to draw upon and bite with acid, as a plate of metal. I was etching a plate at the beginning of 1875. Hamerton.
  2. 3.To sketch; to delineate. [R.] There are many empty terms to be found in some learned writes, to which they had recourse to etch out their system. Locke.
  3. 4.To practice etching; to make etchings.

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