[zahy-luh m, -lem]
- a compound tissue in vascular plants that helps provide support and that conducts water and nutrients upward from the roots, consisting of tracheids, vessels, parenchyma cells, and woody fibers.
Origin of xylem
1870–75; < German, equivalent to Greek xýl(on) wood + -ēma (see phloem)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for xylem
The arrangement of the xylem and the phloëm is different from that of the stem.
The central tissue (x) is called the woody tissue (xylem); the outer, the bast (phloem).
This shows a number of white bars (xylem) surrounded by a more delicate tissue (phloem).
These vessels together with the numerous small thick-walled cells lying between the pitted vessels constitute the xylem.
Just above the xylem there is a group of large and small thin-walled cells.
C19: from Greek xulon wood
Word Origin and History for xylem
"woody tissue in higher plants," 1875, from German Xylem, coined from Greek xylon "wood," of unknown origin.
Online Etymology Dictionary, © 2010 Douglas Harper
- A tissue in vascular plants that carries water and dissolved minerals from the roots and provides support for softer tissues. Xylem consists of several different types of cells: fibers for support, parenchyma for storage, and tracheary elements for the transport of water. The tracheary elements are arranged as long tubes through which columns of water are raised. In a tree trunk, the innermost part of the wood is dead but structurally strong xylem, while the outer part consists of living xylem, and beyond it, layers of cambium and phloem. See more at cambium capillary action. Compare phloem.
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The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.