Is “Breechblock” a Scrabble word?
Yes
BREECHBLOCK
Valid in at least one Scrabble dictionary
Valid in these dictionaries
SOWPODS / CSW
Scrabble UK & International
TWL / NWL
Scrabble North America
Large English Dictionary
General English word list
Meaning of Breechblock
noun
1.The metal block that closes the breech of a breech-loading gun after insertion of the cartridge.