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.
These experiments have revealed hundreds of plants and fungi that contain psychedelic compounds. Ross Andersen, The Atlantic, 12 June 2026 Raggedly cut grass blades have many openings for fungi to enter the plant. Megan Hughes, Better Homes & Gardens, 12 June 2026 Using vast underground networks, the fungi offer vegetation nutrients and water in exchange for their carbon. Andrew Paul, Popular Science, 11 June 2026 And a fungus may be present if the grass has circular, spreading spots with a musty smell. Mallory Carra, The Spruce, 11 June 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

Browse Nearby Words

Cite this Entry

“Fungus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fungus. Accessed 17 Jun. 2026.

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

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster