Congo red

noun
Con·​go red | \ ˈkäŋ-(ˌ)gō- How to pronounce Congo red (audio) \

Definition of Congo red

: an azo dye C32H22N6Na2O6S2 that is red in alkaline and blue in acid solution and that is used especially as an indicator and as a biological stain

First Known Use of Congo red

1885, in the meaning defined above

History and Etymology for Congo red

Congo, territory in Africa

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Time Traveler for Congo red

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The first known use of Congo red was in 1885

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Dictionary Entries Near Congo red

Congo pink

Congo red

Congo root

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Cite this Entry

“Congo red.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Congo%20red. Accessed 18 Jan. 2022.

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More Definitions for Congo red

Congo red

noun
\ ˌkäŋ-(ˌ)gō-ˈred How to pronounce Congo red (audio) \

Medical Definition of Congo red

: an azo dye C32H22N6Na2O6S2 that is red in alkaline and blue in acid solution and that is used in a number of diagnostic tests and especially for the detection of amyloidosis since the injected dye tends to be retained by abnormal amyloid deposits

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