mycelium

my·ce·li·um

noun \mī-ˈsē-lē-əm\

plural -lia \-lē-ə\

Definition of MYCELIUM

: the mass of interwoven filamentous hyphae that forms especially the vegetative body of a fungus and is often submerged in another body (as of soil or organic matter or the tissues of a host); also : a similar mass of filaments formed by some bacteria (as of the genus Streptomyces)

Illustration of MYCELIUM