the word 'timbered' is a straightforward english formation, combining the noun 'timber' with the adjectival suffix '-ed'. its core, 'timber', originates from old english 'timbr', which referred to building material, a structure, or a dwelling, tracing back to proto-germanic 'tem(b)ra-', related to the concept of building. the modern sense of 'timber' as wood prepared for use in construction was already present in middle english. the addition of the suffix '-ed' creates an adjective describing something as being made of or furnished with timber, leading to its primary meaning for buildings. the secondary meaning, describing land as wooded, is a logical extension, as such land supplies the raw material (timber).

Structure: timber (wood) + ed (adjective suffix) - timber: from old english 'timber' meaning "building material, structure," of germanic origin. - ed: a suffix forming adjectives from nouns or verbs, from old english '-ede', '-ode', '-ad'.