he·​min ˈhē-mən How to pronounce hemin (audio)
: a red-brown to blue-black crystalline salt C34H32N4O4FeCl derived from oxidized heme but usually obtained in a characteristic crystalline form from hemoglobin

Word History


International Scientific Vocabulary

First Known Use

circa 1857, in the meaning defined above

Time Traveler
The first known use of hemin was circa 1857

Dictionary Entries Near hemin

Cite this Entry

“Hemin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hemin. Accessed 2 Dec. 2023.

Medical Definition


variants or chiefly British haemin
: a red-brown to blue-black crystalline salt C34H32N4O4FeCl that inhibits the biosynthesis of porphyrin and is used to ameliorate the symptoms of some forms of porphyria

called also protohemin

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