/ Dictionary / Index E estuarine: Meaning and Definition of Find definitions for: es•tu•a•rine Pronunciation: (es'ch-u-rīn", -ur-in), [key] — adj. formed in an estuary. found in estuaries. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: estuarine (Thesaurus) estrus estuary Related Content Daily Word Quiz: stringent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language