The wall around a city is a yergho, which is apparently derived from yer "domain, holdings, territory" plus gho "circle." A wall which divides a territory into parts (such as the Berlin Wall) is also called a tlhoy', even though neither side of it is the interior of a structure. On occasion, for clarity, such a wall is termed a chevwI' tlhoy' "separator wall") or a pIn tlhoy', literally "boss wall," presumably dating back to a time when each subterritory had a specific person in charge."