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thionine

noun

thi·​o·​nine ˈthī-ə-ˌnēn How to pronounce thionine (audio) -nən How to pronounce thionine (audio)
: a dark crystalline basic thiazine dye that is used chiefly as a biological stain

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thionic acid
thionine
thionyl chloride
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“Thionine.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/thionine. Accessed 1 Dec. 2025.

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