The layer of water in a thermally stratified lake that lies below the thermocline, is noncirculating, and remains perpetually cold.
An unfrozen lake's cold, lowermost, stagnant layer of oxygen-poor water that is below the thermocline.
Origin of hypolimnion
- hypo– Greek limnē lake, pool
From American Heritage Dictionary of the English Language, 5th Edition
- From Ancient Greek ὑπο- (hypo-), combining form of ὑπό (hypó, “under”) + λιμνίον (limnion), diminutive of λίμνη (limnē, “lake”).