fungus

noun

fun·​gus ˈfəŋ-gəs 

plural fungi ˈfən-ˌjī  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

Warm, wet soil encourages fungi that attack the plants’ roots. — Nan Sterman, San Diego Union-Tribune, 1 Aug. 2026

Caused by bacteria or fungi, the disease enters the body through tiny openings in the skin — even a thorn’s pinprick — then slowly eats away surrounding tissue and bone. — Helen Branswell, STAT, 30 July 2026

According to their findings detailed in a study published today in The ISME Journal, everything from tiny worms, to hardy tardigrades, to even rock-eating fungi build a vast, complex ecosystem below the Earth’s surface. — Andrew Paul, Popular Science, 29 July 2026

Researchers are even looking beyond barriers, experimenting with cultivating edible fungi in sandy ground to build up organic soil nutrients under bamboo shelter zones. — Mrigakshi Dixit, Interesting Engineering, 27 July 2026

Word History

Etymology

Latin

First Known Use

1527, in the meaning defined above

Phrases Containing fungus

• bracket fungus
• chytrid fungus
• club fungus
• cup fungus
• fungus gnat
• imperfect fungus
• lower fungus
• pore fungus
• sac fungus
• shelf fungus

Rhymes for fungus

• fungous
• tungus

Kids Definition

fungus

noun

fun·​gus ˈfəŋ-gəs 

plural fungi ˈfən-ˌjī  ˈfəŋ-ˌgī  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 

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