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fast red

noun, often capitalized F&R
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Definition of fast red

: any of several fast red azo dyes: such as
a : a monoazo acid dye that dyes wool and silk red

— called also Fast Red A

b : a monoazo acid dye that dyes wool and silk claret and is used chiefly as a biological stain

— called also Bordeaux B, Bordeaux red, Fast Red B

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Dictionary Entries Near fast red

fast/quick study

fast red

fast red base

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Cite this Entry

“Fast red.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fast%20red. Accessed 29 Jun. 2022.

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