Bosporus

American  

[bos-per-uhs] / ˈbɒs pər əs /

Also Bosphorus

noun

1. a strait connecting the Black Sea and the Sea of Marmara. 18 miles (29 km) long.

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Bosporus British  

/ ˈbɒspərəs, ˈbɒsfərəs /

noun

1. a strait between European and Asian Turkey, linking the Black Sea and the Sea of Marmara

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Bosporus Cultural  

1. Strait separating the European and Asian portions of Turkey. The Bosporus is a link between the Black Sea and the Mediterranean Sea.

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It is an important shipping route for Russia, whose northern routes are mostly blocked by ice in winter, and for other nations that border the Black Sea or use any of the many major rivers that flow into it.

Other Word Forms

• Bosporan adjective
• Bosporanic adjective
• Bosporian adjective

Example Sentences

Physical chokepoints include waterways such as the Strait of Hormuz or the Bosporus and Dardanelles, which connect the Mediterranean to the Black Sea, and thus Russian and Ukrainian grain exports.

From The Wall Street Journal • Apr. 12, 2026

Together with the Bosporus Strait, it serves as a vital route for commercial shipping between Europe and Asia.

From BBC • Aug. 8, 2025

On Saturday, authorities at the Bulgarian port of Varna did not confirm whether the Anna-Theresa will enter the port or will continue to the Bosporus Strait.

From Washington Times • Sep. 2, 2023

On Saturday, authorities at the Bulgarian port of Varna did not confirm whether the bulk carrier will enter the port or continue to the Bosporus Strait.

From Seattle Times • Sep. 2, 2023

Mithradates the Great entrusted the Bosporus Cimmerius to his son Machares, who, however, deserted to the Romans.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Slice 3 "Borgia, Lucrezia" to "Bradford, John" by Various