The definition of a cotyledon is the first leaf or set of leaves that sprout from a seed.(noun)
An example of a cotyledon is the first two leaves that sprout from a sunflower seed.
See cotyledon in Webster's New World College Dictionary
Origin: ModL < L, name of a plant < Gr kotylēdōn < kotylē, a hollow, cavity
See cotyledon in American Heritage Dictionary 4
Origin: Latin cotylēdōn, navelwort
Origin: , from Greek kotulēdōn
Origin: , from kotulē, hollow object.
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