cotyledon

American  

[kot-l-eed-n] / ˌkɒt lˈid n /

noun

Botany.

1. the primary or rudimentary leaf of the embryo of seed plants.

2. Anatomy. any of several lobules of the placenta.

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cotyledon British  

/ ˌkɒtɪˈliːdən /

noun

1. a simple embryonic leaf in seed-bearing plants, which, in some species, forms the first green leaf after germination

2. a tuft of villi on the mammalian placenta

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cotyledon Scientific  

/ kŏt′l-ēd′n /

1. A leaf of the embryo of a seed-bearing plant. Most cotyledons emerge, enlarge, and become green after the seed has germinated. Cotyledons either store food for the growing embryo (as in monocotyledons) or absorb food that has been stored in the endosperm (as in other angiosperms) for eventual distribution to the growing parts of the embryo.

2. Also called seed leaf

3. See more at eudicotyledon monocotyledon

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Other Word Forms

• cotyledonal
  adjective
• cotyledonary
  adjective
• cotyledonous
  adjective
• noncotyledonal
  adjective
• noncotyledonary
  adjective
• noncotyledonous
  adjective
• pseudocotyledonal
  adjective
• pseudocotyledonary
  adjective

Etymology

Origin of cotyledon

1535–45; < Latin: navelwort < Greek kotylēdṓn a plant (probably navelwort), literally, a cuplike hollow, derivative of kotýlē cup

Example Sentences

In five days, the “baby” cotyledon leaves were up, with the “true” notched tomato leaves following at day 10.

From Seattle Times • Jan. 27, 2023

Swinger says the sprout, called a cotyledon, only exists for a few days and once it grew slightly the birds didn’t want to eat it anymore.

From Washington Times • Jul. 17, 2016

The cross-section of a cotyledon is, therefore, a triangle whose angles vary with the number composing the fascicle.

From The Genus Pinus by Shaw, George Russell

Some plantlets, as they develop and start to push above the ground, bear along the cotyledon.

From The Library of Work and Play: Gardening and Farming. by Shaw, Ellen Eddy

Bean with one cotyledon removed, after sprouting had begun. a, Seed-coat; b, cotyledon; c, epicotyl; d, hypocotyl; e, endosperm.

From The First Book of Farming by Goodrich, Charles Landon