What is "voynuks"

Voynuks (sometimes called voynugans or voynegans) were members of the privileged Ottoman military social class established in the 1370s or the 1380s. Voynuks were tax-exempt non- Muslim, usually Slavic, and also non-Slavic Vlach Ottoman citizens from the Balkans, particularly from the regions of southern Serbia, Macedonia, Thessaly, Bulgaria and Albania and much less in Bosnia and around the Danube– Sava region. Voynuks belonged to the Sanjak of Voynuk which was not a territorial unit like other sanjaks but a separate organisational unit of the Ottoman Empire.