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

How to clean a humidifier While humidifiers offer clear benefits, standing water inside the tank can become a breeding ground for mold, bacteria, mineral deposits and fungi if the device isn’t cleaned regularly. —Daryl Austin, USA Today, 13 Dec. 2025

According to the outlet, the team of researchers believe that the royal's death began with a chronic skin disease called chromoblastomycosis, which is in an infection under the skin cause by fungi, per the World Health Organization. —Gabrielle Rockson, PEOPLE, 9 Dec. 2025

Histoplasmosis is a lung infection, or pneumonia, caused by breathing in spores of the fungus Histoplasma from the environment, according to the Centers for Disease Control and Prevention. —Diana Leyva, Nashville Tennessean, 9 Dec. 2025

But the fungus forms a fuzz on their wings and muzzles. —Ashley J. Dimella, FOXNews.com, 9 Dec. 2025

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