breechblock
- n a metal block in breech-loading firearms that is withdrawn to insert a cartridge and replaced to close the breech before firing
- The list of Russian firsts which pulls Pyatov up from obscurity starts with the adding machine, anesthesia, Antarctica, atomic fission, runs on to the wedge breechblock and the .
- Lger saw his fill of suffering in World War I, but the image he carried away with him was the dazzling light of a breechblock gleaming in the sun.