1911 Encyclopædia Britannica/Rafter

RAFTER, a beam in a sloping roof to which is attached the framework for the slating, tiling or other external covering (see Roofs). The O.Eng. raefter is cognate with Icel. raftr, Dan. and Swed. rafte or raft, a beam, which, in the special sense of a floating collection of timbers, gives the English “raft.” The ultimate base of these words is the root raf-, to cover, seen in Gr. ὄροφος, roof.