Where does “rozpustnica” come from?

rozpustnica (Polish) comes from Polish -nica, from Old Polish -nica, from Proto-Slavic *-ьnica.

Ancestry of “rozpustnica”, step by step

StepLanguageWordMeaning
1Polish-nicafemale equivalent of -nik
2Old Polish-nicaforms feminine nouns
3Proto-Slavic*-ьnica—
Every word from Proto-Slavic *-ьnica →Every word from Polish -nica →Every word from Old Polish -nica →