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
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An ancient family The mass extinction that caused the dinosaurs’ demise may have created an environment for the king-size fungus to evolve and thrive, according to the study. — Mindy Weisberger, CNN Money, 23 Oct. 2026 The plants and fungi in his garden had dried up, and summer puddles, with their flamboyant biological complexity, had long frozen over. — Molly Herring, Quanta Magazine, 21 Oct. 2026 Mold in coffee refers to tiny fungi that can grow on beans during harvest, processing or storage, producing byproducts called mycotoxins. — Hanna Wickes, Miami Herald, 20 Oct. 2026 Beeswax, honey, and pollen each possess their own particular antimicrobial and chemical properties that, taken together, repel disease and encourage helpful fungi. — Amanda Erickson, STAT, 20 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 27 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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