heartwood

[ hahrt-woo d ]
/ ˈhɑrtˌwʊd /

noun

the hard central wood of the trunk of an exogenous tree; duramen.

Origin of heartwood

First recorded in 1795–1805; heart + wood1
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Examples from the Web for heartwood

British Dictionary definitions for heartwood

heartwood

/ (ˈhɑːtˌwʊd) /

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
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for heartwood

heartwood

[ härtwud′ ]

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.
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