Denes are small valleys or hollows in the ground that usually have a small stream running through them. Synonyms for denes can include gullies, dells, hollows, ravines, canyons, valleys, and clefts. Each of these words describes a specific type of geological formation, but they all share the same general characteristics as denes. Gullies and ravines tend to be narrower and steeper than denes, while valleys and canyons are usually wider and deeper. Dells and hollows are often used to describe smaller, more secluded denes, while clefts describe any narrow opening or crevice formed by geological processes. Overall, these synonyms can help to add variety and precision to descriptions of denes and similar landforms.