thymol blue

noun

: a greenish crystalline compound C27H30O5S derived from thymol and used as an acid-base indicator

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thymol
thymol blue
thymolphthalein
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“Thymol blue.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/thymol%20blue. Accessed 14 Jul. 2025.

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