noun
- the hard central wood of the trunk of an exogenous tree; duramen.
noun
- the central core of dark hard wood in tree trunks, consisting of nonfunctioning xylem tissue that has become blocked with resins, tannins, and oilsCompare sapwood
- The older, nonliving central wood of a tree or woody plant, usually darker and harder than the younger sapwood. Unlike the sapwood, it no longer conducts water, and its main function is the support of the tree.