The ethnonym Turk (Greek: Τούρκοι/Tourkoi, Serbo-Croatian: Turci/Турци, Macedonian: Турчин, Bulgarian: Турчин, Albanian: Turqit) has been commonly used by the non-Muslim Balkan peoples to denote all Muslim people in the region, regardless of their ethno-linguistic background. Most of the Muslims in the Ottoman Empire, however, were indeed ethnic Turks. In the Ottoman Empire, the faith of Islam was the official state religion, with Muslims holding higher rights than non-Muslims. Non-Muslim (dhimmi) ethno-religious legal groups were identified by different millets ("nations").
Turk was also notably used to denote all groups in the region who had been Islamized during the Ottoman rule, especially Muslim Albanians and Slavic Muslims (mostly Bosniaks). For the Balkan Christians, converting to Islam was synonymous with Turkification, succumbing to "Ottoman rule and embracing the Ottoman way of life," hence "to become a Turk". In South Slavic languages, there are also derivative terms, which are seen as more offensive towards Bosniaks, such as poturiti, poturčiti and poturica (all essentially meaning "Turk" or "to turkify").