cortex - definition of cortex by The Free Dictionary

cor·tex (kôr′tĕks′) n. pl. cor·ti·ces (-tĭ-sēz′) or cor·tex·es 1. Anatomy a. The outer layer of an internal organ or body structure, as of the kidney or adrenal gland. b. The outer layer of gray matter that covers the surface of the cerebral hemisphere.

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