Rapids
"Reach of a stream where the flow is very swift and shooting, and where the surface is usually broken by obstructions, but has no actual waterfall or cascade." (United Nations Publications, 2013)
Sources
United Nations Publications. "Glossary of Shared Water Resources (English-Arabic): Technical, Socioeconomic and Legal Terminology." (2013). DOI:https://dx.doi.org/10.18356/70b462ce-en