Colluvy is a geological term that refers to a type of deposit formed by the accumulation of loose soil, rock fragments, and debris at the base of a sloping surface. There are several synonyms for this term that can be used in geological or scientific writing, such as talus, alluvium, sediment, detritus, and debris flow. Talus refers to a similar deposit of large rock fragments that have accumulated at the base of a steep slope or cliff. Alluvium is a term used to describe a deposit of sediment or soil that has been transported by water and deposited in a river or stream bed. Detritus is a term that generally refers to any type of loose debris or waste material. Debris flow is a specific type of colluvial deposit that occurs when water and sediment flow rapidly down a slope.