Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Medical
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

Congo red

play
noun Con·go red \ˈkäŋ-(ˌ)gō-\

Definition of Congo red

  1. :  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



Origin of congo red

Congo, territory in Africa


First Known Use: 1885


Medical Dictionary

Congo red

play
noun Con·go red \ˌkäŋ-(ˌ)gō-ˈred\

Medical Definition of Congo red

  1. :  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




Learn More about congo red


Seen and Heard

What made you want to look up Congo red? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

February 12, 2016

of, relating to, or suggestive of marble

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

image33683556

How much does a batman (the Turkish unit of measurement) weigh?

100 pounds 16.96 pounds 196.5 pounds 2.2 pounds
Name That Thing

10 quick questions: hear them, spell them, and see how your skills compare to the crowd.

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ