toluidine blue

noun

: a basic thiazine dye that is related to methylene blue and is used as a biological stain

Word History

First Known Use

1898, in the meaning defined above

Time Traveler

The first known use of toluidine blue was in 1898

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toluidine blue

toluidine red toner

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“Toluidine blue.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/toluidine%20blue. Accessed 31 Oct. 2025.

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Medical Definition

toluidine blue

noun

: a basic thiazine dye that is related to methylene blue and is used as a biological stain and especially formerly as an antihemorrhagic drug

called also tolonium chloride

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toluidine blue

noun

Word History

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