Keystone
Related Definitions
[n] the central building block at the top of an arch or vault
Related Terms
apse, arcade, arcature, arch, arched roof, archway, basis, bench mark, camber, cardinal point, ceilinged roof, chief thing, climax, concameration, concha, core, cornerstone, cove, crisis, critical point, crux, cupola, dome, essence, essential, essential m