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.
ROUTING INDICATOR
Meaning of ROUTING INDICATOR in English
DOD English dictionary of military terms. Английский словарь военных терминов DOD. 2012