phthalein
/ˈ(f)θeɪlɪɪn/ /ˈ(f)θalɪɪn/ /ˈ(f)θeɪlɪiːn/(also phthaleine, phthaleïne) Chemistry
noun
Any of a series of organic dyes produced by replacing the oxygen atom of one of the C=O groups of phthalic anhydride by two (substituted) phenyl groups. Frequently attributive, especially in phthalein dye.
- Recorded earliest in phenolphthalein..
Origin
Late 19th century; earliest use found in Journal of the Chemical Society. From phthal- + -ein, after German Phtaleïn.