phenolsulfonephthalein


phe•nol•sul•fone•phthal•ein

(ˌfi nɔlˌsʌl foʊnˈθæl in, -i ɪn, -ˈfθæl-, -nɒl-)

n. a bright to dark red crystalline compound, C19H14O5S, slightly soluble in water, alcohol, and acetone: used as an acid-base indicator and as a diagnostic reagent in medicine. Also called phe′nol red′.