Central:

In anatomy and medicine (as elsewhere), central is the opposite of "peripheral" which means away from the center. The word "peripheral" comes from the Greek "peripheria" ("peri-", around or about + "pherein", to bear, carry).

A central line is an infusion tube that is located in or near the heart (centrally in the circulatory system). A Swan-Ganz cather with its tip, for example, in the right atrium and ventricle of the heart is a central line. On the other hand, a peripheral line is located on the periphery of the circulatory system. An ordinary IV (intravenous) catheter is a peripheral line.

The human nervous system consists of the central nervous system (CNS) and the peripheral nervous system (PNS). The brain and spinal cord make up the CNS. The PNS contains the nerves outside the CNS.