Where does “долбоёбище” come from?

долбоёбище (Russian) comes from Russian долбоёб, from Russian еба́ть, from Old East Slavic ети, from Proto-Slavic *jetì, from Proto-Balto-Slavic jebtei, from Proto-Indo-European h₃yébʰeti, from Proto-Indo-European h₃yebʰ- — to copulate, have sex.

Ancestry of “долбоёбище”, step by step

StepLanguageWordMeaning
1Russianдолбоёбdickhead, fuckwit, dumbass, dipshit, motherfucker stupid person
2Russianеба́тьto fuck
3Old East Slavicетиto copulate, to fuck
4Proto-Slavic*jetì
5Proto-Balto-Slavicjebteito copulate, fuck
6Proto-Indo-Europeanh₃yébʰetito copulate, to fuck
7Proto-Indo-Europeanh₃yebʰ-to copulate, have sex
Every word from Proto-Indo-European h₃yebʰ-Every word from Proto-Indo-European h₃yébʰetiEvery word from Proto-Balto-Slavic jebtei