Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio.
the block in a breech-loading gun which when closed receives the force of the combustion of the charge
Used by arrangement with John Wiley & Sons, Inc.
The 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.
The metal part that closes the breech end of the barrel of a breechloading gun and that is removed to insert a cartridge and replaced before firing.