A group of letters assigned to indicate: (a) the geographic location of a station; (b) a fixed headquarters of a command, activity, or unit at a geographic location; and (c) the general location of a tape relay or tributary station to facilitate the routing of traffic over the tape relay networks. 2. In a message header, an address, i.e., group of characters, that specify routing instructions for the transmission of the message to its final destination. Note: Routing indicators may also include addresses of intermediate points.