phenolphthalein

noun
phe·​nol·​phtha·​lein | \ ˌfē-nᵊl-ˈtha-lē-ən How to pronounce phenolphthalein (audio) , -ˈtha-ˌlēn, -ˈthā- How to pronounce phenolphthalein (audio) \

Definition of phenolphthalein

: 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

Examples of phenolphthalein in a Sentence

Recent Examples on the Web Those ingredients included things like sibutramine, an appetite suppressant that was taken off the market due to the risk for strokes, as well as the laxative phenolphthalein. Sarah Jacoby, SELF, 17 Dec. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'phenolphthalein.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of phenolphthalein

1875, in the meaning defined above

History and Etymology for phenolphthalein

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

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Time Traveler for phenolphthalein

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The first known use of phenolphthalein was in 1875

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Dictionary Entries Near phenolphthalein

phenology

phenolphthalein

phenol red

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Cite this Entry

“Phenolphthalein.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/phenolphthalein. Accessed 8 Aug. 2022.

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More Definitions for phenolphthalein

phenolphthalein

noun
phe·​nol·​phtha·​lein | \ ˌfēn-ᵊl-ˈthal-ē-ən How to pronounce phenolphthalein (audio) , -ˈthal-ˌēn How to pronounce phenolphthalein (audio) , -ˈthāl- \

Medical Definition of phenolphthalein

: 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

More from Merriam-Webster on phenolphthalein

Britannica.com: Encyclopedia article about phenolphthalein

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