Where does “український” come from?
український (Ukrainian) comes from Ukrainian Украї́на, from Old East Slavic Украина, from Russian Украи́на, from Slavic Оукраина, from Old East Slavic краи, from Proto-Slavic krajь, from Proto-Slavic krojiti, from Proto-Balto-Slavic krájīˀtei — to sift, to separate.
Ancestry of “український”, step by step