eosinPronunciation: /ˈiːə(ʊ)sɪn/Definition of eosin noun [mass noun] a red fluorescent dye that is a bromine derivative of fluorescein, or one of its salts or other derivatives. Origin: late 19th century: from Greek ēōs 'dawn' + -in1eosin in other Oxford dictionaries Definition of eosin in the US English dictionary
