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bean seed germinating


1. Botany A leaf of the embryo of a seed plant, which upon germination either remains in the seed or emerges, enlarges, and becomes green. Also called seed leaf.
2. Anatomy One of the lobules constituting the uterine side of the mammalian placenta, consisting mainly of a rounded mass of villi.

[Latin cotylēdōn, navelwort, from Greek kotulēdōn, from kotulē, hollow object.]

cot′y·le′don·ar′y (-ēd′n-ĕr′ē), cot′y·le′don·al (-ēd′n-əl), cot′y·le′do·nous (-ēd′n-əs) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
Tissue cultures in Passiflora edulis through adventitious organogenesis (A-E) by using cotyledonal explants and in Passiflora cincinnata through somatic embryogenesis (F-J) from zygotic embryos.
schizophylla can be classified as hypogeal crypto cotyledonal germination of the remote-tubular type, based in the concept developed by Tomlinson (1961), with the expansion of an absorption organ inside de seed with a further elongation of the cotyledon petiole which leads the seedling to the surface due to the differentiation of the shoot and root primordia (Figure 5-A-B-C).