mycelium

American  

[mahy-see-lee-uhm] / maɪˈsi li əm /

noun

Mycology.

mycelia plural

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

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mycelium British  

/ ˈmaɪsɪˌlɔɪd, maɪˈsiːlɪəm /

noun

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

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mycelium Scientific  

/ mī-sē′lē-əm /

mycelia plural

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.

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Other Word Forms

Derived Forms

• myceloid
  adjective
• mycelial
  adjective

Inflected Forms

noun

• mycelia
  plural

Etymology

Origin of mycelium

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

Example Sentences

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

From Barron's • Nov. 13, 2025

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

From Barron's • Nov. 13, 2025

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

From BBC • Sep. 29, 2025

Weil appeared on Fungi Perfecti promotional materials for mycelium products holding large mushrooms on a 2016 poster.

From Los Angeles Times • Jun. 18, 2025

You can’t dig up a mushroom to study it because the mycelium is too tiny and delicate.

From "The Omnivore's Dilemma" by Michael Pollan