breech /brut/; britf/ n back part of a rifle or gun barrel, where the cartridge or shell is placed: (槍炮的) 后膛 (裝子彈或炮彈的地方)： a Leading, gun, loaded at the ~, not through the muzzle. 由后膛裝彈的槍炮。 '~-block n block of steel that closes the ~ of a gun. (槍炮之) 問體; 檜炮問。