a particular complex anatomical part of a living thing and its construction and arrangement

a major part of the central nervous system which conducts sensory and motor nerve impulses to and from the brain; a long tubelike structure extending from the base of the brain through the vertebral canal to the upper lumbar region

membranous duct connecting the fetus with the placenta

a structure resembling a cord that suspends the testis within the scrotum and contains the vas deferens and other vessels and nerves