a vertical series of sieve cells in the phloem, specialized for the conduction of food materials.
a single sieve cell.
Origin of sieve tube
First recorded in 1870–75
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for sieve tube
botany an element of phloem tissue consisting of a longitudinal row of thin-walled elongated cells with perforations in their connecting walls through which food materials pass
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