The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.
a lengthwise growth in plants as a result of cell division in the formative tissue (meristem), located below the top of the organ—for example, in the internodes of the stalks of grasses and at the base of the leaves.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.