Solid wood is lumber milled directly from the trees. It is the most direct, uncomposited, and natural version of wood available.

Solid wood differs from other woods because no other additives are used in its creation. Woods such as plywood may come from trees but the wood layers are recomposited into a different wood material, changing its strength and use. Other wood products such as wood laminate and use substances to alter the strength and durability synthetically.