Tidal stream is a term used to describe the flow of water in estuaries or coastal areas due to the gravitational pull of the moon and sun. It is an important natural phenomenon that affects marine life and plays a crucial role in various activities like shipping, fishing, and renewable energy production. There are several synonyms for tidal stream, including tidal flow, tidal current, tidal drift, and tidal race. These terms are often used interchangeably, but they do have some subtle differences in their definition. Overall, they all refer to the movement of water that is influenced by the ebb and flow of tides.