Merseians

Every Merseian has a personal name, a nickname and a Vach and some also have a military rank. Thus, we learn of the Merseian prisoner on Daedalus in The Game Of Empire -

Personal name: Eidhafor;
nickname: the Bold;
Vach: Dathyr;
rank: Fodaich.

Later, we learn that the Merseian ambassador to Terra is Chwioch the Dandy and that current members of the Roidhun's Grand Council include:

Tachwyr the Dark, Hand of the Vach Dathyr and Protector of the Council;
Odhar the Curt;
Alwis Longtail;
Gwyanafon of Brightwater.

Tachwyr addresses the members on multiple screens of a communication set on a towertop of his castle so that he can simultaneously overlook the lands of his Vach beneath its ancient battle banners: high tech barbarism. Appropriately, a fangryf hunts above and his sons stand at attention below. 

In space:

Cyntath Gadrol Cannonshield, Vach Invory, commands a task force from the dreadnaught Ardwyr;

Qanryf Bryadan Arrowswift, Vach Hallen, commands a squadron from the cruiser Tryntaf;

Afal Uroch the Lucky, Vach Rueth, commands an escadrille of twenty gunboats launched from Tryntaf.

We are not told why Merseians address each other as "foreseer."