Question: Whats it called when fresh and saltwater meet?
Disambiguated questions and answers: question: Whats the water called when fresh and saltwater meet and mix?
Whats the coastal body called when fresh water from a river and saltwater from the sea meet?
Whats it called when fresh and saltwater meet in freshwater aquifers, possibly degrading groundwater?
Whats it called when fresh and saltwater meet because saltwater moves inland due to a loss in freshwater column pressure?
answer: brackish
brackish water
estuary
saltwater intrusion
groundwater extraction
Natural Questions answer: estuaries (from the Wikipedia article "Brackish water")