Where does “błocisko” come from?

błocisko (Polish) comes from Polish błoto, from Old Polish błoto, from Proto-Slavic bolto, from Proto-Balto-Slavic balta.

Ancestry of “błocisko”, step by step

StepLanguageWordMeaning
1Polishbłotomud
2Old Polishbłotomud
3Proto-Slavicboltoswamp; mud
4Proto-Balto-Slavicbalta
Every word from Proto-Balto-Slavic baltaEvery word from Proto-Slavic boltoEvery word from Old Polish błoto