: a crystalline betaine C9H15N3O2S that is found especially in ergot and blood

called also thioneine

Browse Nearby Words

Cite this Entry

“Ergothioneine.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/ergothioneine. Accessed 8 Jul. 2026.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!