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mycelium

American  
[mahy-see-lee-uhm] / maɪˈsi li əm /

noun

Mycology.

plural

mycelia

  1. the mass of hyphae that form the vegetative part of a fungus.

mycelium British  
/ ˈmaɪsɪˌlɔɪd, maɪˈsiːlɪəm /

noun

  1. the vegetative body of fungi: a mass of branching filaments (hyphae) that spread throughout the nutrient substratum

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
mycelium Scientific  
/ mī-sē′lē-əm /

plural

mycelia

  1. The mass of fine branching tubes (known as hyphae) that forms the main growing structure of a fungus. Visible structures like mushrooms are reproductive structures produced by the mycelium.

Other Word Forms

  • mycelial adjective
  • myceloid adjective

Etymology

Origin of mycelium

1830–40; < New Latin, equivalent to Greek myk- myc- + ( h ) ḗl ( os ) wart, nail + New Latin -ium -ium

Vocabulary lists containing mycelium

Microbiology - High School

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Feeding on the waste, the mycelium grows into the desired shape.

From Barron's • Nov. 13, 2025

These are placed into moulds, where mycelium, the root-like structure of fungi, takes over.

From Barron's • Nov. 13, 2025

They included a structure grown from mycelium, the root network of fungus.

From BBC • Sep. 29, 2025

Or could a mushroom also be synonymous with its fungal roots, otherwise known as mycelium, from which the fruiting bodies sprout?

From Los Angeles Times • Jun. 18, 2025

Most of it is underground, consisting of a network of microscopic cells called mycelium.

From "The Omnivore's Dilemma" by Michael Pollan

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.