variants or reishi mushroom or less commonly Reishi or Reishi mushroom
plural reishis or reishi mushrooms also Reishis or Reishi mushrooms
: a bracket fungus (such as Ganoderma sichuanense or G. lucidum) of East Asia that forms glossy reddish-brown fanlike fruiting bodies (as on the bases of hardwood trees) which are used especially in folk and herbal medicine
Noelle also enjoys reishis, as she makes homemade tinctures and teas out of them.Cathy Jakicic
Although you can eat any of these mushrooms whole, chaga and reishi mushrooms have a bitter taste, so they are most easily enjoyed steeped in tea or as a powder added to other foods or beverages.Christy Brissette
In the wild, Reishi grows in old or dead hardwood trees such as plum and oaks.Ella Wilson
Reishi's richly colored caps, which are high in fiber, vitamins and amino acids, are too tough for culinary purposes but have been used medicinally for thousands of years.Elena Conis

Word History

Etymology

borrowed from Japanese

First Known Use

1889, in the meaning defined above

Time Traveler
The first known use of reishi was in 1889

Browse Nearby Words

Cite this Entry

“Reishi.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reishi. Accessed 26 Aug. 2026.

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