Where does “jedynaczka” come from?

jedynaczka (Polish) comes from Polish Jedynak, from Polish jedyny, from Old Polish jedyny, from Proto-Slavic edìnъ, from Proto-Balto-Slavic edīˀnas, from Proto-Balto-Slavic aiˀnas, from Proto-Indo-European óynos — one; single.

Ancestry of “jedynaczka”, step by step

StepLanguageWordMeaning
1PolishJedynakonly child
2Polishjedynyonly
3Old Polishjedynyonly
4Proto-Slavicedìnъone
5Proto-Balto-Slavicedīˀnas—
6Proto-Balto-Slavicaiˀnasone
7Proto-Indo-Europeanóynosone; single
Every word from Proto-Indo-European óynos →Every word from Proto-Balto-Slavic aiˀnas →Every word from Proto-Balto-Slavic edīˀnas →