Main Entry: phe·nol·phtha·lein

Pronunciation: \ˌfē-n^əl-ˈtha-lē-ən, -ˈtha-ˌlēn, -ˈthā-\

Function: noun

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

Date: 1875

: 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