Where does “Dęby” come from?

Dęby (Polish) comes from Polish dąb, from Proto-Slavic dǫbъ, from Proto-Indo-European dʰanw-.

Ancestry of “Dęby”, step by step

StepLanguageWordMeaning
1Polishdąboak
2Proto-Slavicdǫbъoak tree; oak
3Proto-Indo-Europeandʰanw-—
Every word from Proto-Indo-European dʰanw- →Every word from Proto-Slavic dǫbъ →Every word from Polish dąb →