- a movable piece of metal for closing the breech in certain firearms.
Origin of breechblock
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for breechblock
Breechblock—a movable piece which closes the breech of a cannon.Artillery Through the Ages
- a metal block in breech-loading firearms that is withdrawn to insert the cartridge and replaced to close the breech before firing