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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.
References in periodicals archive ?
Eggs or larvae of early stages have been found abundantly only on very young seedlings (with cotyledonal leaves and 1-4 true leaves) and on one occasion it required chemical control but neonate larvae can be washed away from leaves when these plants are watered daily, thus reducing survival.