stopping-out

from The Collaborative International Dictionary of English v.0.48
Stopping-out \Stop"ping-out`\, n.
   A method adopted in etching, to keep the acid from those
   parts which are already sufficiently corroded, by applying
   varnish or other covering matter with a brush, but allowing
   the acid to act on the other parts.
   [1913 Webster]
    

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