Definition of cortex
1a(1) : the outer or superficial part of an organ or bodily structure (such as the kidney, adrenal gland, or cerebellum or a bone) especially : cerebral cortex
(2) : the proteinaceous usually pigmented layer of a hair below the cuticle
b : the outer part of some organisms (such as paramecia)
2 : a plant bark or rind (such as cinchona) used medicinally
3a : the typically parenchymatous layer of tissue external to the vascular tissue and internal to the corky or epidermal tissues of a green plant broadly : all tissues external to the xylem
b : an outer or investing layer of various algae, lichens, or fungi
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Time Traveler for cortex
The first known use of cortex was in 1677
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