xylem

noun xy·lem \ ˈzī-ləm , -ˌlem \

|Updated on: 9 Jun 2018

Definition of xylem

: a complex tissue in the vascular system of higher plants that consists of vessels, tracheids, or both usually together with wood fibers and parenchyma cells, functions chiefly in conduction of water and dissolved minerals but also in support and food storage, and typically constitutes the woody element (as of a plant stem) — compare phloem

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Recent Examples of xylem from the Web

Around the edges ran thick, vertical strands containing xylem, the tubelike structures that carry water through many plants.

— daisy yuhas, Scientific American, "Ancient Tree Structure Is Like a Forest unto Itself," 1 Jan. 2018
As the cladoxylopsids grew, these columns of xylem split themselves apart—most likely to supply water to the expanding plant.

— daisy yuhas, Scientific American, "Ancient Tree Structure Is Like a Forest unto Itself," 1 Jan. 2018
Maple sap flows through the tree’s water-transport system, called the xylem, inside minuscule vertical tubes about a thousandth of an inch in diameter.

— helen czerski, WSJ, "The Freeze and Thaw That Give Us Maple Syrup," 21 Mar. 2018
The strands, known as xylem, are tubes that carry water from the roots of a tree to its branches and leaves.

— brigit katz, Smithsonian, "Ancient Trees “Ripped Their Skeletons Apart” To Grow," 26 Oct. 2017
The trunk is a single cylindrical shaft made up of hundreds of woody strands called xylem, which conduct water from the roots to the branches and leaves.

— dennis normile, Science | AAAS, "The world’s first trees grew by splitting their guts," 23 Oct. 2017
New xylem grow in rings at the periphery of the trunk just behind the bark, adding girth so the tree can get taller.

— dennis normile, Science | AAAS, "The world’s first trees grew by splitting their guts," 23 Oct. 2017
In theory, this keeps air from entering the water-carrying xylem tubes inside the flower stem.

— jeff lowenfels, Alaska Dispatch News, "Make the most of this exceptional summer for Alaska flowers," 4 Aug. 2017
Cane bark (phloem) and wood (xylem) damage can occur in grapevines at temperatures from minus 4 to minus 13.

— eric degerman, idahostatesman, "Harsh winter takes heavy toll on Treasure Valley vines," 14 Apr. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'xylem.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.