What is the term used for the addition of land because of wind or water?

The correct term for the addition of land as a result of natural processes such as wind or water is "accretion." Accretion occurs when sediment or soil is deposited in a particular area, gradually expanding the land. This process can take place in various environments, such as along riverbanks, coastlines, or deltas, where water movement contributes to the accumulation of land.

Erosion, on the other hand, refers to the removal of soil or rock from one location, which is the opposite of what happens during accretion. Alluvion also relates to the deposits made by flowing water, but it is a more specific term that refers to the sediment deposited in a body of water, not the overall process of land addition. Reclamation involves converting land that is unsuitable for building or use into usable land but does not directly pertain to the natural accumulation of land through wind or water.

Thus, recognizing that "accretion" represents the natural process of land gain provides a clear understanding of how land can be added over time.