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

This is the one cotyledon of the corn.

From The First Book of Farming by Goodrich, Charles Landon

There, in the seed, the cotyledon remains, imbibing nourishment from the softened albumen, and transmitting it to the growing root below and new-forming leaves above.

From The Elements of Botany For Beginners and For Schools by Gray, Asa

There is some difference of opinion as to which structure or structures represent the cotyledon.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" by Various