Where does “kosátko” come from?

kosátko (Czech) comes from Czech kose, from Czech koš, from Old Czech koš, from Proto-Slavic kǫsъ, from Proto-Slavic kǫsati, from Proto-Slavic kǫ̑sъ — piece.

Ancestry of “kosátko”, step by step

StepLanguageWordMeaning
1Czechkoseblackbird chick
2Czechkošbasket
3Old Czechkošbasket
4Proto-Slavickǫsъpiece
5Proto-Slavickǫsatito bite
6Proto-Slavickǫ̑sъpiece
Every word from Proto-Slavic kǫ̑sъ →Every word from Proto-Slavic kǫsati →Every word from Proto-Slavic kǫsъ →