Medical Dictionary
phthalein
noun phtha·lein \ˈthal-ē-ən, ˈthal-ˌēn, ˈthāl-\
Medical Definition of PHTHALEIN
: any of various xanthene dyes (as phenolphthalein or fluorescein) that are intensely colored in alkaline solution
Seen & Heard
What made you want to look up phthalein? Please tell us where you read or heard it (including the quote, if possible).