endogen

from The Century Dictionary.

• noun A plant belonging to one of the large primary classes into which the vegetable kingdom is divided: so named from the belief that the fibrovascular bundles were developed only about the center of the stem, in distinction from the exogens or “outside growers”; a monocotyledon.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Bot.) A plant which increases in size by internal growth and elongation at the summit, having the wood in the form of bundles or threads, irregularly distributed throughout the whole diameter, not forming annual layers, and with no distinct pith. The leaves of the endogens have, usually, parallel veins, their flowers are mostly in three, or some multiple of three, parts, and their embryos have but a single cotyledon, with the first leaves alternate. The endogens constitute one of the great primary classes of plants, and included all palms, true lilies, grasses, rushes, orchids, the banana, pineapple, etc. See exogen.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun botany A plant which increases in size by internal growth and elongation at the summit, having the wood in the form of bundles or threads, irregularly distributed throughout the whole diameter, not forming annual layers, and with no distinct pith.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a monocotyledonous flowering plant; the stem grows by deposits on its inside