Where does “Истанбул” come from?

Истанбул (Bulgarian) comes from Ottoman Turkish استانبول, from Greek εἰς τὴν Πόλιν.

Ancestry of “Истанбул”, step by step

StepLanguageWordMeaning
1Ottoman Turkishاستانبول
2Greekεἰς τὴν Πόλιν
Every word from Greek εἰς τὴν ΠόλινEvery word from Ottoman Turkish استانبول