phenolphthalein (redirected from Phenylpthalein)

phenolphthalein /phe·nol·phthal·ein/ (fe?nol-thal´en) a cathartic and pH indicator, with a range of 8.5 to 9.0.

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phe·nol·phthal·ein (fnl-thln, -thl-n, -thln, -thl-n)

n.

A white or pale yellow crystalline powder that is used as an acid-base indicator and a laxative.

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phenolphthalein

1. an acid-base indicator dye; it is colorless below pH 8.5, but turns red above pH 9.0.

2. in monogastric animals, a cathartic administered orally, usually with a bulk laxative such as agar. When ingested by ruminants causes the urine to change color to red on exposure to air.