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 ˈfəŋ-gə-səz 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 fungus causes a severe infection associated with a 60% to 70% fatality rate, even with aggressive medical intervention, according to a systematic review published in Medical Mycology. — Khloe Quill, FOXNews.com, 16 Oct. 2026 The fatal fungi were seen in Idaho in the fall of 2021, the Idaho Statesman previously reported. — Hali Smith, Idaho Statesman, 15 Oct. 2026 The ergot theory, despite being debunked within a year of being published, has continued to spread and thrive like fungus on rye. — Jennifer Byrne, Popular Science, 15 Oct. 2026 There’s work coming out of our group here in Amsterdam led by Vasilis Kokkoris, who’s an incredible geneticist in many ways studying mycorrhizal fungi. — Quanta Magazine, 15 Oct. 2026 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

Phrases Containing fungus

Rhymes for fungus

See All Rhymes for fungus

Browse Nearby Words

fungous
fungus
fungused
See all Nearby Words

Cite this Entry

“Fungus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fungus. Accessed 20 Oct. 2026.

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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

More from Merriam-Webster on fungus

Britannica.com: Encyclopedia article about fungus

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