Britannica AI Icon
Adding us as a Preferred Source tells Google you trust our content, so our articles show up more often in your Google Search, Discover feed, and AI Overviews.
verifiedCite
While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions.
Select Citation Style

mycelium, the mass of branched, tubular filaments (hyphae) of fungi. The mycelium makes up the thallus, or undifferentiated body, of a typical fungus. It may be microscopic in size or developed into visible structures, such as brackets, mushrooms, puffballs, rhizomorphs (long strands of hyphae cemented together), sclerotia (hard, compact masses), stinkhorns, toadstools, and truffles. At a certain stage it produces spores, directly or through special fruiting bodies.

The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Meg Matthias.