(Anatomy)the outer layer of the cerebrum (the cerebral cortex), composed of folded grey matter and playing an important role in consciousness (剖)脑皮层 ■an outer layer of another organ or body part such as a kidney (the renal cortex), the cerebellum, or a hair (肾、小脑或头发等的)皮层;皮质 ■(Botany)an outer layer of tissue immediately below the epidermis of a stem or root (植)皮层