neutral red

noun

: a basic dye used chiefly as a biological stain and acid-base indicator

Word History

First Known Use

1890, in the meaning defined above

Time Traveler

The first known use of neutral red was in 1890

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Cite this Entry

Style

“Neutral red.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/neutral%20red. Accessed 19 Apr. 2025.

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Medical Definition

neutral red

noun

: a basic phenazine dye used chiefly as a biological stain and acid-base indicator

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