meromixis
/ˌmɛrə(ʊ)ˈmɪksɪs/Limnology
noun
The property (of a lake) by which water below a certain depth does not circulate during overturn owing to its high density (usually the result of a high salt concentration).
Origin
1940s; earliest use found in Ecological Monographs. From mero- + ancient Greek μίξις mixing, after earlier meromictic.