What is the term for the natural increase of land along the shore due to water movement?

The correct term for the natural increase of land along the shore due to water movement is accretion. This process occurs when sediment is deposited by the movement of water, gradually leading to the extension of land into bodies of water. Accretion typically results from the actions of current, waves, or other hydrological forces that carry and deposit materials such as sand and silt.

This natural phenomenon has implications for property rights and land ownership, particularly in coastal areas, as land that forms due to accretion may become part of adjacent properties. In contrast, alluvion refers specifically to the increase of land as a result of the gradual deposits by rivers, while erosion is the process of land being worn away by natural forces. Depositional shift, though it might imply the movement of sediment, is not a recognized term in the context of land formation associated with water movement, making accretion the most accurate term in this scenario.