Where does “Czajka” come from?

Czajka (English) comes from Polish Czajka, from Old Polish czajka, from Proto-Slavic čajьka, from Proto-Slavic -ьka, from Proto-Balto-Slavic -ikaʔ, from Proto-Indo-European -ikeh₂.

Ancestry of “Czajka”, step by step

StepLanguageWordMeaning
1PolishCzajkanorthern lapwing
2Old Polishczajkanorthern lapwing
3Proto-Slavicčajьkagull
4Proto-Slavic-ьka—
5Proto-Balto-Slavic-ikaʔ—
6Proto-Indo-European-ikeh₂—
Every word from Proto-Indo-European -ikeh₂ →Every word from Proto-Slavic -ьka →Every word from Proto-Slavic čajьka →