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

With the amount of traffic a hotel has, carpets can harbor dirt, dust mites, stains, bacterial, mold, and fungi. — Brandee Gruener, Southern Living, 27 June 2026

Social media is full of testimonials, but veterinarians and researchers tell a more complicated story about what this fungus can and cannot do. — Samantha Agate, Kansas City Star, 26 June 2026

Reishi mushrooms have long been linked to allergy relief, and a growing body of research is starting to explain why people turn to the ancient fungi during hay fever season. — Samantha Agate, Miami Herald, 26 June 2026

The mushroom is part of a broader family of medicinal fungi long used in human and veterinary practice. — Samantha Agate, Charlotte Observer, 25 June 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