'Cotyledon' definitions:

Definition of 'cotyledon'

(from WordNet)
noun
Embryonic leaf in seed-bearing plants [syn: cotyledon, seed leaf]

Definition of 'Cotyledon'

From: GCIDE
  • Cotyledon \Cot`y*le"don\ (k?t`?-l?"d?n), n. [Gr.??? a cupshaped hollow, fr. ???. See Cotyle.]
  • 1. (Anat.) One of the patches of villi found in some forms of placenta. [1913 Webster]
  • 2. (Bot.) A leaf borne by the caulicle or radicle of an embryo; a seed leaf. [1913 Webster]
  • Note: Many plants, as the bean and the maple, have two cotyledons, the grasses only one, and pines have several. In one African plant (Welwitschia) the cotyledons are permanent and grow to immense proportions. [1913 Webster]