mush·​room | \ ˈməsh-ˌrüm How to pronounce mushroom (audio) , -ˌru̇m; chiefly Northern and Midland US -ˌrün; dialectal ˈmə-shə-ˌrüm, -ˌru̇m, -ˌrün \

Definition of mushroom

 (Entry 1 of 2)

1a : an enlarged complex aboveground fleshy fruiting body of a fungus (such as a basidiomycete) that consists typically of a stem bearing a pileus especially : one that is edible
b : fungus
2 : upstart
3 : something resembling a mushroom


mushroomed; mushrooming; mushrooms

Definition of mushroom (Entry 2 of 2)

intransitive verb

1a : to well up and spread out laterally from a central source
b : to become enlarged or extended : grow
2 : to collect wild mushrooms
3 : to spring up suddenly or multiply rapidly

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Examples of mushroom in a Sentence

Noun cut up some mushrooms for the salad Verb Interest in local history is suddenly mushrooming. Her hobby mushroomed into a thriving business. He goes mushrooming in the spring every year.
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Recent Examples on the Web: Noun Try our just-as-delicious vegetarian smoky mushroom stroganoff. Katlyn Moncada, Better Homes & Gardens, "6 Beef Stroganoff Recipes for You to Enjoy the Comforting Dish at Home," 19 Mar. 2021 From smoky Hungarian mushroom soup to herbaceous baked cod to cheesy chickpea pancakes, let these 55 one-dish meals do the heavy lifting. Ali Francis, Bon Appétit, "55 One-Dish Meals That Won’t Leave You With an Overflowing Sink," 17 Mar. 2021 The man was Paul Stamets and the object of his desire was an Agarikon mushroom. Emily Wilson, Bon Appétit, "My Favorite Magazine Is a Mushroom Catalog—Yes, You Heard That Right," 9 Apr. 2021 That trust is the linchpin of an international effort that has seen the dreams mushroom. Rohan Preston, Star Tribune, "Minnesota 'saint' gardener uses plant sales to transform lives of youngsters in Tanzania," 19 Mar. 2021 Place the mushroom filling in a strainer for 30 minutes to drain off any excess liquid. Janelle Bitker, San Francisco Chronicle, "5 fun facts about S.F.'s Chinatown from the triumphant new Mister Jiu's cookbook," 16 Mar. 2021 Another mushroom in this blend is Maitake, which is referred to as the Dancing Mushroom. Lindsey Bartlett, Forbes, "Cannabis Brand Cookies Enters The CBD And Mushroom Medicine Game With Caps Line," 24 Feb. 2021 There’s even a crabby-looking Pokémon with a parasitic mushroom on its back. Washington Post, "Parasites may not be cute and cuddly, but they need saving too, scientists say," 14 Dec. 2020 The mushroom is just the fruiting body, similar to an apple on a tree. Corryn Wetzel, Smithsonian Magazine, "Watch an Amazing Time-Lapse of Growing Mushrooms," 2 Nov. 2020 Recent Examples on the Web: Verb To justify that number, the math shows, Coinbase would need to mushroom into the biggest financial exchange in the world. Shawn Tully, Fortune, "The mathematical impossibility of Coinbase justifying a $100 billion valuation," 12 Apr. 2021 Two years on, streaming revenues have continued to mushroom, even through a pandemic, and the valuations slapped on Universal have grown in tandem. Tim Ingham, Rolling Stone, "Is Universal Music Worth $29 Billion? $49 Billion? Even $100 Billion?," 22 Mar. 2021 Across the city, at unlicensed bars, police officers routinely break up house parties and other events, including D.J. live streams, which can mushroom into de facto parties. New York Times, "How the Illegal Rave Scene Thrives During the Pandemic," 19 Mar. 2021 So in just two years, the U.S. debt will mushroom from $16.8 trillion to a minimum of $23.3 trillion, a jump of $6.5 trillion or almost 40% in just 24 months. Shawn Tully, Fortune, "The U.S. now has a debt level that rivals Italy’s," 14 Jan. 2021 The book predicts that the organizations will continue to mushroom. Doug Maccash,, "Need a guide to New Orleans Mardi Gras marching groups? New photo book 'I Wanna Do That!' can help," 1 Dec. 2020 All of Arizona's COVID-19 metrics remain far below the levels hit during the state’s summer peak for the virus, but experts caution that the increases seen in recent weeks could again quickly mushroom out of control. Stephanie Innes, The Arizona Republic, "Coronavirus in Arizona is spreading at its fastest rate since June. Here's what we know," 21 Oct. 2020 In San Francisco, homelessness program directors created a special unit to tackle prevention in the street, worrying that an infection in just one camp or shelter could mushroom. Kevin Fagan,, "Surprise: Homeless people not getting coronavirus in the disastrous waves experts had feared," 10 July 2020 Cases were also mushrooming elsewhere in the state: Epidemiologists were deployed to investigate six COVID-19 deaths in the southwest Georgia city of Albany that were later traced to local funerals. Keren Landman/undark, Popular Science, "Inside the struggles and successes of one Georgia county’s fight with COVID-19," 10 Apr. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mushroom.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of mushroom


15th century, in the meaning defined at sense 1a


1893, in the meaning defined at sense 1a

History and Etymology for mushroom


Middle English musheron, from Anglo-French musherum, musseron, from Late Latin mussirion-, mussirio

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Time Traveler for mushroom

Time Traveler

The first known use of mushroom was in the 15th century

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Statistics for mushroom

Last Updated

4 May 2021

Cite this Entry

“Mushroom.” Dictionary, Merriam-Webster, Accessed 7 May. 2021.

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More Definitions for mushroom



English Language Learners Definition of mushroom

 (Entry 1 of 2)

: a fungus that is shaped like an umbrella especially : one that can be eaten



English Language Learners Definition of mushroom (Entry 2 of 2)

: to increase or develop very quickly
: to collect wild mushrooms


mush·​room | \ ˈməsh-ˌrüm How to pronounce mushroom (audio) , -ˌru̇m \

Kids Definition of mushroom

 (Entry 1 of 2)

: a part of a fungus that bears spores, grows above ground, and suggests an umbrella in shape


mushroomed; mushrooming

Kids Definition of mushroom (Entry 2 of 2)

: to appear or develop suddenly or increase rapidly The town's population has mushroomed.


mush·​room | \ ˈməsh-ˌrüm How to pronounce mushroom (audio) , -ˌru̇m How to pronounce mushroom (audio) \

Medical Definition of mushroom

1 : an enlarged complex fleshy fruiting body of a fungus (as most basidiomycetes) that arises from an underground mycelium and consists typically of a stem bearing a spore-bearing structure especially : one that is edible — compare toadstool

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