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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Cite this Entry

“Thionine.” Medical Dictionary, Merriam-Webster, Accessed 29 Mar. 2023.

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