[bos-per-uh
s] 
| a strait connecting the Black Sea and the Sea of Marmara. 18 mi. (29 km) long. |
[bos-fer-uhs] . [bos-puh-ran-ik] , Bos⋅po⋅ri⋅an [bo-spawr-ee-uhn, -spohr-] , adjective Strait separating the European and Asian portions of Turkey. The Bosporus is a link between the Black Sea and the Mediterranean Sea.
Note: 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.