'Breechblock' definitions:
Definition of 'breechblock'
From: WordNet
noun
A metal block in breech-loading firearms that is withdrawn to insert a cartridge and replaced to close the breech before firing [syn: breechblock, breech closer]
Definition of 'Breechblock'
From: GCIDE
- Breechblock \Breech"block\, n. The movable piece which closes the breech of a breech-loading firearm, and resists the backward force of the discharge. It is withdrawn for the insertion of a cartridge, and closed again before the gun is fired. [1913 Webster]