What denotes the gradual, steady downhill movement of soil and loose rock material?

The term that accurately describes the gradual, steady downhill movement of soil and loose rock material is soil creep. This process involves the slow, persistent movement of soil due to gravity, which can be exacerbated by factors such as moisture, plant growth, and freeze-thaw cycles. Soil creep often occurs over long periods, and its effects may not be immediately apparent but can lead to significant alterations in the landscape, such as tilting of trees, fences, or structures.

To understand why this answer is fitting, consider how soil creep is characterized by its gradual nature. It typically results in a slow, continuous movement rather than sudden or rapid mass movements, which differentiates it from other forms of slope movement like earth flow or debris falls that involve more abrupt processes.

In summary, soil creep is a fundamental concept in understanding mass wasting processes in geology, representing one of the slower forms of earth movement that can impact soil stability and landscape evolution.