cortex

noun

cor·​tex ˈkȯr-ˌteks How to pronounce cortex (audio)
plural cortices ˈkȯr-tə-ˌsēz How to pronounce cortex (audio) also cortexes
1
a(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
3
a
: 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

Examples of cortex in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
However, many parts of the brain or cortex are not fully active if external simulations aren’t present. Laura Baisas, Popular Science, 6 Nov. 2024 Areas responsible for motor control and coordination light up as your motor cortex learns how to direct your muscles efficiently. William A. Haseltine, Forbes, 1 Nov. 2024 Unlike traditional hair masks that sit outside each strand, this one works inside the cortex to restore strength and elasticity. Christa Joanna Lee, Allure, 23 Oct. 2024 The cortex can’t regrow and continues to shrink throughout life. Patrick Martin, NBC News, 9 Sep. 2024 See all Example Sentences for cortex 

Word History

Etymology

Latin cortic-, cortex bark — more at cuirass

First Known Use

circa 1676, in the meaning defined at sense 1a(1)

Time Traveler
The first known use of cortex was circa 1676

Dictionary Entries Near cortex

Cite this Entry

“Cortex.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cortex. Accessed 30 Nov. 2024.

Kids Definition

cortex

noun
cor·​tex ˈkȯr-ˌteks How to pronounce cortex (audio)
plural cortices ˈkȯrt-ə-ˌsēz How to pronounce cortex (audio) or cortexes
1
: an outer or surrounding layer of an organ or body part
the cortex of the kidney
especially : the outer layer of gray matter of the cerebrum
2
: the layer of tissue outside the xylem and phloem and inside the corky or epidermal tissues of a vascular plant
also : all tissues external to the xylem

Medical Definition

cortex

noun
cor·​tex ˈkȯr-ˌteks How to pronounce cortex (audio)
plural cortices ˈkȯrt-ə-ˌsēz How to pronounce cortex (audio) also cortexes
1
a
: the outer or superficial part of an organ or body structure (as the kidney, adrenal gland, or a hair)
especially : cerebral cortex
b
: the outer part of some organisms (as paramecia)
2
a
: a plant bark or rind (as cinchona) used medicinally
b
: the peel of any of several fruits
used especially in the writing of medical prescriptions

More from Merriam-Webster on cortex

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