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Webster 1913 Edition
Hammer-beam
Ham′mer-beamˊ
(-bēmˊ)
, Noun.
(Gothic Arch.)
A member of one description of roof truss, called hammer-beam truss, which is so framed as not to have a tiebeam at the top of the wall. Each principal has two hammer-beams, which occupy the situation, and to some extent serve the purpose, of a tiebeam.