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 As a result, the study found, typing required less brain activity in the visual and motor cortices. Aria Bendix, NBC News, 27 Jan. 2024 The study published by the Lancet, found that 94% of patients diagnosed with Posterior Cortical Atrophy, or PCA, a neurodegenerative condition that impairs one's vision and mainly affects the occipital and parietal cortex, also had Alzheimer's. Julia Gomez, USA TODAY, 26 Jan. 2024 Musical activities trigger the auditory cortex (a.k.a. Ayana Underwood, SELF, 14 Feb. 2024 Using the Allen Human Brain Atlas, these researchers looked at gene activity in the frontal cortex. Diana Gitig, Ars Technica, 19 Dec. 2023 These small molecules are hypothesized to penetrate the cortex of the hair and crosslink hair proteins while excluding some frizz-inducing water from entering the hair. Allure, 30 Nov. 2023 The somatosensory cortex enables the brain to sense what the body touches. Joshua Rapp Learn, Discover Magazine, 19 Sep. 2023 This network is a collection of brain regions—including parts of the insula and the anterior cingulate cortex—that prior studies had found were associated with distress in the face of social exclusion. Diana Kwon, Scientific American, 15 Aug. 2023 The researchers found thinning across much of the cortex—a discovery that particularly worries Kawata. TIME, 5 Feb. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'cortex.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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 18 Mar. 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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