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phenolsulfonphthalein

noun phe·nol·sul·fon·phtha·lein

variants: or chiefly British

phenolsulphonphthalein

\-ˌsəl-fän-ˈthal-ē-ən, -ˈthal-ˌēn, -ˈthāl-\play

Medical Definition of phenolsulfonphthalein

: a red crystalline compound C₁₉H₁₄O₅S used chiefly as a test of kidney function and as an acid-base indicator—called also phenol red

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