All ex-Yugoslav republics are speaking the same Serbo-Croatian language, despite calling it Serbian, Croatian, Bosnian etc. Even today, after 20 years of separation, their languages are closer to each other than some South and North Italian dialects. Genetically they are mostly the same population too. Only Albanians in Kosovo and Metohia are exception in both cases.

So, technically Bosniaks, Croats, Macedonians, Montenegrins, Serbs, and Slovenians are South Slavs, or literally Yugo-Slavs.