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phenolphthalein

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noun phe·nol·phtha·lein \ˌfē-nəl-ˈtha-lē-ən, -ˈtha-ˌlēn, -ˈthā-\

Definition of phenolphthalein

  1. :  a white or yellowish-white crystalline compound C20H14O4 used in analysis as an indicator because its solution is brilliant red in alkalies and is decolorized by acids and in medicine as a laxative



Origin of phenolphthalein

International Scientific Vocabulary phenol + phthalein any of various xanthene dyes, from phthalic acid


First Known Use: 1875


Medical Dictionary

phenolphthalein

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noun phe·nol·phtha·lein \ˌfēn-əl-ˈthal-ē-ən, -ˈthal-ˌēn, -ˈthāl-\

Medical Definition of phenolphthalein

  1. :  a white or yellowish white crystalline compound C20H14O4 that is used in analysis as an indicator because its solution is brilliant red in alkalies and is decolorized by acids and that is used in medicine as a laxative




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