Definition of cortex
corticesplay \ˈkȯr-tə-ˌsēz\ or
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 cuticleb : 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 xylemb : an outer or investing layer of various algae, lichens, or fungi
Recent Examples of cortex from the Web
These individuals showed an increase in brain activity in the cortex, the outermost layer of the brain, which is involved in learning.
As expected, the act of improv led to a surge of activity in a variety of neural areas, including the premotor cortex and the inferior frontal gyrus.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cortex'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
CORTEX Defined for English Language Learners
Definition of cortex for English Language Learners
medical : the outer layer of an organ in the body and especially of the brain
Medical Definition of cortex
1a: the outer or superficial part of an organ or body structure (as the kidney, adrenal gland, or a hair); especially : cerebral cortexb: the outer part of some organisms (as paramecia)
2a: a plant bark or rind (as cinchona) used medicinallyb: the peel of any of several fruits—used especially in the writing of medical prescriptions
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