Definition of "apothecaries' weight" [apothecaries' weight]

• A system of weights used in pharmacy and based on an ounce equal to 480 grains and a pound equal to 12 ounces. It has been largely replaced by measures of the metric system. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.