A river that enters a sea or estuary and is this affected by tides; at times, water will flow upstream.

(geology) A fast-flowing river characterized by a deep, narrow erosion pattern forming a V-shaped channel or valley.

A city in Bristol County, Massachusetts, United States. / A river in South Dakota, United States.

Any marine turtle that inhabits rivers.

Alternative form of riverbank

Onchocerciasis.

Alternative form of riverbed

Alternative form of riverbed

A river in North America flowing to the north from Lake Erie to Lake Ontario and including the Niagara Falls.

The European river lamprey (Lampetra fluviatilis).