plural fungi
ˈfən-ˌjī 
ˈfəŋ-ˌgī
also funguses
ˈfəŋ-gə-səz
ˈfəŋ-ˌgī
also funguses
ˈfəŋ-gə-səz
often attributive
: any of a kingdom (Fungi) of saprophytic and parasitic spore-producing eukaryotic typically filamentous organisms formerly classified as plants that lack chlorophyll and include molds, rusts, mildews, smuts, mushrooms, and yeasts
Examples of fungus in a Sentence
Recent Examples on the Web
The Brooks Range and icy coastline of Prudhoe Bay have functionally isolated the tundra’s plant-fungus partnerships from the rest of Alaska.
—
Quanta Magazine, 6 Apr. 2026
Caused by a fungus, the leaf spot is unattractive but not life-threatening to the plant.
—Steve Bender, Southern Living, 10 Mar. 2026
And a fungus may be present if the grass has circular, spreading spots with a musty smell.
—Mallory Carra, The Spruce, 8 Mar. 2026
Additionally, since potting soil is rarely completely sterile and usually contains some moisture when packaged, this moisture can promote the growth of mold, fungus, or anaerobic bacteria, especially in moist or humid conditions.
—Sj McShane, Martha Stewart, 3 Mar. 2026
See All Example Sentences for fungus
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Quanta Magazine, 6 Apr. 2026
Caused by a fungus, the leaf spot is unattractive but not life-threatening to the plant.
—Steve Bender, Southern Living, 10 Mar. 2026
And a fungus may be present if the grass has circular, spreading spots with a musty smell.
—Mallory Carra, The Spruce, 8 Mar. 2026
Additionally, since potting soil is rarely completely sterile and usually contains some moisture when packaged, this moisture can promote the growth of mold, fungus, or anaerobic bacteria, especially in moist or humid conditions.
—Sj McShane, Martha Stewart, 3 Mar. 2026
See All Example Sentences for fungus
Cite this Entry
“Fungus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fungus. Accessed 8 Apr. 2026.
Copy CitationKids Definition
fungus
noun
fun·gus
ˈfəŋ-gəs
1
: any of a kingdom of living things (as molds, rusts, mildews, smuts, and mushrooms) that lack chlorophyll, are parasitic or live on dead or decaying organic matter, and were formerly considered plants
2
: infection with a fungus
fungus
adjective
Medical Definition
fungus
noun
fun·gus
ˈfəŋ-gəs
plural fungi
ˈfən-ˌjī also ˈfəŋ-ˌgī
also funguses
ˈfəŋ-gə-səz
often attributive
1
: any of the kingdom Fungi of saprophytic and parasitic spore-producing eukaryotic typically filamentous organisms formerly classified as plants that lack chlorophyll and include molds, rusts, mildews, smuts, mushrooms, and yeasts
2
: infection with a fungus
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