/floo res"ee in, flaw-, floh-/ , n. Chem.
an orange-red, crystalline, water-insoluble solid, C 20 H 12 O 5 , that in alkaline solutions produces an orange color and an intense green fluorescence: used to trace subterranean waters and in dyes.
Also, fluoresceine . Also called resorcinolphthalein .
[ 1875-80; FLUORESCE + -IN 2 ]