Where does “Istrău” come from?

Istrău (Romanian) comes from Hungarian Esztró, from Old Church Slavonic островъ, from Proto-Slavic ostrovъ, from Proto-Indo-European strow-.

Ancestry of “Istrău”, step by step

StepLanguageWordMeaning
1HungarianEsztró—
2Old Church Slavonicостровъisland
3Proto-Slavicostrovъstreamlined; river island; island
4Proto-Indo-Europeanstrow-—
Every word from Proto-Indo-European strow- →Every word from Proto-Slavic ostrovъ →Every word from Old Church Slavonic островъ →