/ Dictionary / Index P phenolsulfonephthalein: Meaning and Definition of Find definitions for: phe•nol•sul•fone•phthal•ein Pronunciation: (fē"nôl-sul"fōn-thal'ēn, -ē-in, -fthal'-, -nol-), [key] — n. Chem. a bright to dark red crystalline compound, CHOS, slightly soluble in water, alcohol, and acetone: used as an acid-base indicator and as a diagnostic reagent in medicine. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. phenolphthalein phenom Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language