From PIE *dem- (to build)—the same root behind domestic, dome, and German 'Zimmer' (room).
Wood prepared for use in building and carpentry; also, growing trees regarded as a source of wood.
From Old English 'timber' (building, structure, building material), from Proto-Germanic *timrą (building material, wood), from PIE *dem- (to build). The same root gives Greek 'domos' (house), Latin 'domus' (home), and English 'domestic.' Key roots: *dem- (Proto-Indo-European: "to build, to construct a house").