fungus

American  

[fuhng-guhs] / ˈfʌŋ gəs /

noun

• fungi,
  plural
• funguses
  plural

1. any of a diverse group of eukaryotic single-celled or multinucleate organisms that live by decomposing and absorbing the organic material in which they grow, comprising the mushrooms, molds, mildews, smuts, rusts, and yeasts, and classified in the kingdom Fungi or, in some classification systems, in the division Fungi (Thallophyta) of the kingdom Plantae.

2. Pathology. a spongy, abnormal growth, as granulation tissue formed in a wound.

---

adjective

1. fungal.

   a fungus infection of the toenails.

fungus British  

/ ˈfʌŋɡəs /

noun

1. any member of a kingdom of organisms (Fungi) that lack chlorophyll, leaves, true stems, and roots, reproduce by spores, and live as saprotrophs or parasites. The group includes moulds, mildews, rusts, yeasts, and mushrooms

2. something resembling a fungus, esp in suddenly growing and spreading rapidly

3. pathol any soft tumorous growth

---

fungus Scientific  

/ fŭng′gəs /

• fungi
  plural

1. Any of a wide variety of organisms that reproduce by spores, including the mushrooms, molds, yeasts, and mildews. The spores of most fungi grow a network of slender tubes called hyphae that spread into and feed off of dead organic matter or living organisms. Fungi absorb food by excreting enzymes that break down complex substances into molecules that can be absorbed into the hyphae. The hyphae also produce reproductive structures, such as mushrooms and other growths. Some fungi (called perfect fungi) can reproduce by both sexually produced spores and asexual spores; other fungi (called imperfect fungi or deuteromycetes) are thought to have lost their sexual stage and can only reproduce by asexual spores. Fungi can live in a wide variety of environments, and fungal spores can survive extreme temperatures. Fungi exist in over 100,000 species, nearly all of which live on land. They can be extremely destructive, feeding on almost any kind of material and causing food spoilage and many plant diseases. Although fungi were once grouped with plants, they are now considered a separate kingdom in taxonomy.

2. See Table at taxonomy

---

Other Word Forms

Derived Forms

• fungic
  adjective
• fungus-like
  adjective
• funguslike
  adjective

Inflected Forms

Nouns

• fungi
  plural
• funguses
  plural

Etymology

Origin of fungus

First recorded in 1520–30; from Latin: “fungus, mushroom”; perhaps akin to Greek spóngos, sphóngos sponge

Explanation

Is there a fungus among us? A fungus is a simple organism that's not an animal or a plant. A delicious mushroom is one kind of fungus, while another type of fungus causes nasty infections. The plural of fungus is fungi, so when you order a pizza you can request it "with extra fungi" if you like. Mold, yeast, and mildew are all types of fungi, and there are plenty of edible fungi as well, including truffles and portobello mushrooms. While a fungus may look like a plant, it doesn't go through photosynthesis like plants do and it reproduces through spores.

Example Sentences

See Examples For:

fungus fungi funguses

Pancho often took him there, teaching Óscar when to fertilize and how to identify deadly fungus.

From Los Angeles Times ● Sep. 6, 2026

In 2025, the UK's first confirmed record of a rare fungus species, Russula blumiana, was made in Epping Forest.

From BBC ● Aug. 30, 2026

If mold is a concern, home buyers should consider hiring a mold specialist or asking home inspectors to test for mold, if possible, and stay vigilant about the potential growth of the fungus.

From MarketWatch ● Aug. 15, 2026

Leafcutter ants cultivate fungus for food, while ants of the Lasius genus tend aphids for their sweet secretions “like domestic cattle.”

From The Wall Street Journal ● Aug. 3, 2026

We don’t know exactly why or when the fungus produces a mushroom either.

From "The Omnivore's Dilemma" by Michael Pollan

Picking the fungi can disrupt the forest's ecosystem, which helps recycle nutrients, support wildlife, and preserve some 55,000 ancient trees.

From BBC ● Aug. 30, 2026

Social media posts showcasing fungi picking is affecting a forest's ecosystem, according to officials.

From BBC ● Aug. 30, 2026

A large survey of plant-based foods and beverages sold in the UK has found that mycotoxins, toxic compounds naturally produced by fungi, are widespread across vegetarian and vegan products.

From Science Daily ● Aug. 28, 2026

Alongside microorganisms commonly found on human skin, the team identified fungi and salt-adapted archaea.

From Science Daily ● Aug. 4, 2026

If the fungi could cure lockjaw, he’d feel a softening in those joints.

From "The Undead Fox of Deadwood Forest" by Aubrey Hartman

After snowball Earth, titanosaurs and dawn redwoods and humongous funguses appear.

From Scientific American ● Sep. 24, 2021

The illnesses most frequently reported by migrants who make it across the jungle are foot funguses, gastrointestinal problems and respiratory infections.

From Seattle Times ● Sep. 16, 2021

In 1962, Rachel Carson published the book “Silent Spring,” which convincingly argued that chemicals used to kill insects, funguses and pests were also killing birds and harming the environment.

From Washington Times ● Jun. 4, 2016

This makes your entire body hypersensitive to all forms of irritants, including weather changes, certain food proteins, and funguses.

From New York Times ● Jul. 20, 2010

It has a stout sucker, with a honeysuckle grown into it—coming up among the moss, where the great white vase-shaped funguses grew up in the autumn.'

From Dynevor Terrace: or, the clue of life — Volume 1 by Charlotte Mary Yonge

Related Words

• affliction
• canker
• decay
• eyesore
• infestation
• mildew
• pest
• scourge