Tidal strait

A tidal strait is a strait connecting two oceans or seas through which a tidal current flows.

Tidal currents are usually unidirectional but sometimes are bidirectional.

Tidal straits, though they are narrow seaways, are technically not rivers.

In them, currents develop because of elevation differences between the water basins at both ends.

[1] Tides sometimes allow sediments to collect in tidal straits.