A tributary
The Yukon river
The Seine River empties into the English Channel.
The MacKenzie River Watershed which empties into the Arctic includes the Liard and Peel Rivers. The Yukon River empties into the Bering Sea and the Pacific Watershed includes the Alsek and Tatshenshini Rivers.
It empties into the Atchafalaya and Mississippi Rivers.
The Hudson River
One river is the Ganges River. Technically it is a distributary of the Ganges River, the Padma that empties into the Bay. Also there are several other rivers that flow through the Ganges Plain that enter the Bay of Bengal such as the Meghna and the Jamuna.
What river empties into the Pamlico Sound? The Tar and Neuse rivers empty into the Pamlico Sound
Mississippi River. That is the only river that empties into the gulf of Mexico.
It is the other way around. The Sabine river flows into the southeastern Mississippi river about 300 miles before it empties into to the Gulf of Mexico.
The Missouri does, the Colorado does not. It empties instead into the Sea of Cortez.
An estuary is an inlet of water where a river empties into an ocean or sea. It is formed from the freshwaters of rivers and stream, protected from storms, ocean waves and winds.
Many rivers flow into the Mississippi River. The two largest are the Missouri from the west and the Ohio from the east.