eosin

noun
eo·​sin | \ ˈē-ə-sən How to pronounce eosin (audio) \
variants: or less commonly eosine \ ˈē-​ə-​sən How to pronounce eosine (audio) , -​ˌsēn \

Definition of eosin

1 : a red fluorescent dye C20H8Br4O5 obtained by the action of bromine on fluorescein and used especially in cosmetics and as a toner also : its red to brown sodium or potassium salt used especially as a biological stain for cytoplasmic structures
2 : any of several dyes related to eosin

First Known Use of eosin

1866, in the meaning defined at sense 1

History and Etymology for eosin

International Scientific Vocabulary, from Greek ēōs dawn

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Time Traveler for eosin

The first known use of eosin was in 1866

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More Definitions for eosin

eosin

noun
eo·​sin | \ ˈē-ə-sən How to pronounce eosin (audio) \
variants: also eosine \ -​sən How to pronounce eosine (audio) , -​ˌsēn How to pronounce eosine (audio) \

Medical Definition of eosin

1 : a red fluorescent dye C20H8Br405 obtained by the action of bromine on fluorescein and used especially in cosmetics and as a toner also : its red to brown sodium or potassium salt used especially as a biological stain for cytoplasmic structures
2 : any of several dyes related to eosin

More from Merriam-Webster on eosin

Britannica.com: Encyclopedia article about eosin

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