bosporus

bosporus is a   Noun

Definition:

[1] A strait or narrow sea between two seas, or a lake and a seas; as, the Bosporus (formerly the Thracian Bosporus) or Strait of Constantinople, between the Black Sea and Sea of Marmora; the Cimmerian Bosporus, between the Black Sea and Sea of Azof. [Written also Bosphorus.]

Synonyms: