phloxine

noun

phlox·​ine ˈfläk-ˌsēn  -sən 

: either of two acid dyes or their sodium salts that are derivatives of eosin and are used chiefly as biological stains and organic pigments:

a

: one containing two atoms of chlorine in each molecule

called also phloxine B

b

: one containing four atoms of chlorine in each molecule