Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio.
a poisonous, bright-green powder made by reacting sodium arsenite with copper sulfate and acetic acid: used chiefly as an insecticide
Origin: after Paris
Used by arrangement with John Wiley & Sons, Inc.
nounThe American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
A poisonous emerald-green powder, C4H6As6Cu4O16, used as a pigment, insecticide, and wood preservative.