Where does “sьrdь-ko” come from?

sьrdь-ko (Proto-Slavic) comes from Proto-Balto-Slavic śirˀdís, from Proto-Indo-European ḱḗr — heart.

Ancestry of “sьrdь-ko”, step by step

StepLanguageWordMeaning
1Proto-Balto-Slavicśirˀdísheart
2Proto-Indo-Europeanḱḗrheart
Every word from Proto-Indo-European ḱḗr →Every word from Proto-Balto-Slavic śirˀdís →
sьrdь-ko — Etymology, Origin & Word History | Etymology Explorer