eosin

1. (organic chemistry) A red, acidic dye commonly used in histological stains.Examples: "Thus the fluorescence of the familiar dye eosin can be excited quite well by ultra-violet or short-wave blue light, but is much better excited by visible green light with a wavelength close to that of the emitted radiation."; "Eosins are acid xanthene or phthalein dyes. Eosin Y, eosin B, phloxine and erythrosin (which unlike other eosins, is halogenated with iodine), are the common members of this group of dyes."; "The hematoxylin and eosin stain (H&E) is the most widely used histological stain."countableuncountable