A vazak was a title with Orion society, functioning as a provincial governor and in some cases as a monarch.
The vazaks of Rigel VII (Kolar) were in open revolt against the Emperor of the Vaj ("Empire"). They remained strong but still subject to his tenuous authority, while he lead his armies to besiege their diburnite fortresses. But both the Emperor and the vazaks rejected Federation interference in their ancient Orion traditions.
The Vazak of Zamiar ruled as a monarch over the Orion population of Rigel IV (Zamiar). This was hereditary position. Many Humans of that planet also swore allegiance to the Vazak, preferring the looser Orion way of life. In practice, however, both Orion and Human subjects did what they pleased and were not bound by the Vazak's commands. (Decipher RPG module: Worlds)