Casemate

Case"mate (?), n. [F. casemate, fr. It. casamatta, prob. from casa house + matto, f. matta, mad, weak, feeble, dim. from the same source as E. -mate in checkmate.]

1. (Fort.) A bombproof chamber, usually of masonry, in which cannon may be placed, to be fired through embrasures; or one capable of being used as a magazine, or for quartering troops.

2. (Arch.) A hollow molding, chiefly in cornices.