gymnosperm
[jim-nuh-spurm]
- a vascular plant having seeds that are not enclosed in an ovary; a conifer or cycad.
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Compare angiosperm.
Origin of gymnosperm
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
gymnosperm
- any seed-bearing plant in which the ovules are borne naked on the surface of the megasporophylls, which are often arranged in cones. Gymnosperms, which include conifers and cycads, are traditionally classified in the division Gymnospermae but in modern classifications are split into separate phylaCompare angiosperm
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Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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Word Origin and History for gymnosperm
Online Etymology Dictionary, © 2010 Douglas Harper
gymnosperm
[jĭm′nə-spûrm′]
- Any of a group of seed-bearing plants whose ovules are not enclosed in an ovary, but are exposed on the surface of sporophylls or similar structures. Each ovule may contain several eggs, all of which may be fertilized and start to develop in a process known as polyembryony. In most seeds, however, only a single embryo survives. The reproductive structures of many gymnosperms are arranged in cones. The gymnosperms do not form a distinct monophyletic grouping, but simply include all the seed-bearing plants that are not angiosperms. In addition to several extinct groups, there are four very diverse living gymnosperm phyla: the conifers, the cycads, the ginkgo (surviving in a single species), and the gnetophytes. Compare angiosperm. See more at seed-bearing plant.
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