fungus

noun

fun·​gus ˈfəŋ-gəs How to pronounce fungus (audio)
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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The dinosaur had unknowingly exposed the inside of the tree to fungus, wood-chewing insects and other hazards that could take hold in the wood and slowly make the tree’s own body hostile to itself. Riley Black, Smithsonian Magazine, 27 Feb. 2025 The rust fungus seems like a natural occurrence, especially as the leaves decline in the fall. Tom MacCubbin, Orlando Sentinel, 15 Feb. 2025 The fungus, named Gibellula attenboroughii, infects and kills the spiders, then uses the arachnid’s body to spread its spores. Ashley Strickland, CNN, 15 Feb. 2025 Dandruff is a mild form of seborrheic dermatitis caused by an overgrowth of the yeast (fungus) Malassezia. Heidi Cope, Health, 4 Feb. 2025 See All Example Sentences for fungus

Word History

Etymology

Latin

First Known Use

1527, in the meaning defined above

Time Traveler
The first known use of fungus was in 1527

Browse Nearby Words

Cite this Entry

“Fungus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fungus. Accessed 23 Mar. 2025.

Kids Definition

fungus

noun
fun·​gus ˈfəŋ-gəs How to pronounce fungus (audio)
plural fungi ˈfən-ˌjī How to pronounce fungus (audio) ˈfəŋ-ˌgī How to pronounce fungus (audio) also funguses
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 How to pronounce fungus (audio)
plural fungi
ˈfən-ˌjī also ˈfəŋ-ˌgī
also funguses ˈfəŋ-gə-səz How to pronounce fungus (audio)
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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