Where does “Половраг” come from?

Половраг (Bulgarian) comes from Russian овраг, from Old East Slavic врагъ, from Old Church Slavonic врагъ, from Proto-Slavic vȏrgъ, from Proto-Slavic verťi, from Latin vertere, from Latin verto, from Proto-Italic wertō — to burn; to cover, heed, notice; squirrel.

Ancestry of “Половраг”, step by step

StepLanguageWordMeaning
1Russianоврагravine
2Old East Slavicврагъan enemy, foe; the devil
3Old Church Slavonicврагъan enemy, foe; the devil
4Proto-Slavicvȏrgъfoe, enemy
5Proto-Slavicverťito roll, turn; to throw, cast
6Latinvertereinflection of vertō: ## third-person plural...
7LatinvertoI turn, revolve; I turn around; I reverse
8Proto-Italicwertōto turn
9Proto-Indo-Europeanwert-to turn, to rotate
10Proto-Indo-Europeanwer-to burn; to cover, heed, notice; squirrel
Every word from Proto-Indo-European wer-Every word from Proto-Indo-European wert-Every word from Proto-Italic wertō