has role has role fluorescein (acid form) CHEBI:172923 chebi_ontology fluorescein (free acid) 2-(3-hydroxy-6-oxoxanthen-9-yl)benzoic acid A xanthene dye that is highly fluorescent and commonly used as a fluorescent tracer. fluorescein acid 2-(3-hydroxy-6-oxo-xanthen-9-yl)benzoic acid benzoic acids organic heterotricyclic compound phenols hydroxy monocarboxylic acid radioopaque medium xanthene dye cyclic ketone fluorescent dye