py·​ro·​gal·​lol ˌpī-rō-ˈga-ˌlȯl How to pronounce pyrogallol (audio)
-ˈgȯ- How to pronounce pyrogallol (audio)
: a poisonous bitter crystalline phenol C6H6O3 with weak acid properties that is usually obtained by pyrolysis of gallic acid and used especially as a mild reducing agent (as in photographic developing)

Word History


International Scientific Vocabulary pyro- + gallic (acid) + -ol entry 1

First Known Use

1868, in the meaning defined above

Time Traveler
The first known use of pyrogallol was in 1868

Dictionary Entries Near pyrogallol

Cite this Entry

“Pyrogallol.” Dictionary, Merriam-Webster, Accessed 15 Jul. 2024.

Medical Definition


: a poisonous crystalline phenol C6H6O3 formerly used as a topical antimicrobial (as in the treatment of psoriasis)

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