/ Dictionary / Index H hypolimnion: Meaning and Definition of Find definitions for: hy•po•lim•ni•on Pronunciation: (hī"pu-lim'nē-on", -nē-un, hip"u-), [key] — pl. -ni•a (in certain lakes) the layer of water below the thermocline. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. hypokinesia hypolithic Related Content Daily Word Quiz: loquacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language