In anatomy and zoology the cortex (Latin: “bark”, “rind”, “shell” or “husk”) is the outermost (or “superficial”) layer of an organ. Organs with well-defined cortical layers include kidneys, adrenal glands, ovaries, the thymus, and portions of the brain, including the cerebral cortex, the most well-know of all cortices.

The cerebral cortex is the thin gray surface layer of the cerebellum, consisting of an outer molecular layer or stratum moleculare, a single layer of Purkinje cells (the ganglionic layer), and an inner granular layer or stratum granulosum.