(kor′teks″ )

(kort′ĭ-sēz″)
pl. cortices [L. cortex, stem cortic-, rind]

1. The outer layer of an organ as distinguished from the inner medulla, as in the adrenal gland, kidney, ovary, lymph node, and thymus.
2. The outer layer of a structure, as a hair or the lens of the eye.
3. In the brain, a surface sheet of layered or laminated gray matter, as in the outermost sector of the cerebral and cerebellar hemispheres.
4. The outer superficial portion of the stem or root of a plant.