The first known name of the city is Byzantium (Greek: Byzántion), originating from the name of the king, Byzas, whose colony founded it around 660 BC. After Constantine the Great made it the new eastern capital of the Roman Empire in 330 AD, the city became widely known as Constantinopolis (Constantinople), which, as the Latinized form of Konstantinoúpolis, means the "City of Constantine". He also attempted to promote the name Nea Roma ("New Rome"), but this did not attain widespread usage. Constantinople remained the most common name for the city in the West until the establishment of the Turkish Republic, and Kostantiniyye (Ottoman Turkish) was the primary name used by the Ottomans during their rule. Nevertheless, the use of Constantinople to refer to the city during the Ottoman period (from the mid-15th century) is now considered politically incorrect, even if not historically inaccurate, by Turks.
By the 19th century, the city had acquired a number of other names used by either foreigners or Turks. Europeans used Constantinople to refer to the whole of the city, but used the name Stamboul—as the Turks also did—to describe the walled peninsula between the Golden Horn and the Sea of Marmara. Pera (from the Greek word for "across") was used to describe the area between the Golden Horn and the Bosphorus, but Turks also used the name Beyo?lu, which is still in use today. Islambol (meaning either "City of Islam" or "Full of Islam") was sometimes colloquially used to refer to the city, and was even engraved on some Ottoman coins, but the belief that it was the precursor to the present name, ?stanbul, is belied by the fact that the latter existed well before the former and even predates the Ottoman and Muslim conquest of the city.
Etymologically, the name ?stanbul (Turkish pronunciation: , colloquially ) derives from the Medieval Greek phrase pronounced, which means "to the city". This reflected its status as the only major city in the vicinity, much in the same way people today often colloquially refer to their nearby urban centers as "the City". An alternative view is that the name evolved directly from the name Constantinople, with the first and third syllables dropped. In modern Turkish, the name is written as ?stanbul, with a dotted ?, as the Turkish alphabet distinguishes between a dotted and dotless I. Also, while in English the stress is on the first syllable (Is), in Turkish it is on the second syllable (tan).?stanbul was officially adopted as the sole name of the city in 1930. A person from the city is an ?stanbullu (plural: ?stanbullular), although Istanbulite is used in English.