かいきょう海峡kaikyou
1.

A narrow body of water that connects two larger bodies of water, surrounded on either side by land.

2.

A sea area that is constricted by land on both sides, facilitating the movement of water and vessels between distinct maritime regions.

3.

A marine passage that serves as a conduit between two different seas, typically characterized by its reduced width compared to surrounding waters.

Example:

アメリカンインディアンの祖先は、ベーリング海峡を経由してアジアから米大陸へ渡った。

かんもんかいきょう関門海峡kanmonkaikyou
1.

A navigable waterway that separates the islands of Honshu and Kyushu, serving as a critical point for maritime transportation and trade in Japan.

2.

A strategic strait that connects the Seto Inland Sea with the Tsushima Strait, playing a vital role in the movement of vessels and goods between the two major islands of Japan.

3.

An important geographic feature known for its strong tidal currents, which influences both local fishing practices and the dynamics of regional navigation.