/ Dictionary / Index S serous fluid: Meaning and Definition of Find definitions for: se'rous flu'id Pronunciation: [key] any of various clear, watery fluids in the body. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. serous serous membrane Related Content Daily Word Quiz: sinister Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language