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
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 For the best flavor, use a combination of various wild mushrooms. oregonlive, "13 Thanksgiving gravy recipes, including ones to make-ahead, that use pan drippings," 24 Nov. 2019 However, his favorite dish is Magic Mushrooms, made with a mix of seasonal mushrooms, garam masala and coconut milk. Grace Wong,, "South Asian pop-up Wazwan lands permanent home at Politan Row, plus more Chicago restaurant openings," 20 Nov. 2019 Gamberi Portabella, probably the fussiest dish on the menu, kept it together nonetheless with a silky toss of mushrooms, spinach and lemon cream sauce over jumbo shrimp stuffed with crab and fried crispy. Mike Sutter,, "Review: Gennaro’s Trattoria gives Canyon Lake a solid Italian restaurant option north of San Antonio," 14 Nov. 2019 Fantastic Fungi Documentary explores the medicinal and environmental benefits of mushrooms. Matt Cooper, Los Angeles Times, "Movie openings in L.A. this week: ‘The Current War’ and more," 20 Oct. 2019 For every 4 oz. can of mushrooms there can be an average of 20 or more maggots of any size. Sandee Lamotte, CNN, "Bugs, rodent hair and poop: How much is legally allowed in the food you eat every day?," 4 Oct. 2019 Authorities seized nearly 38 pounds of methamphetamine, 108 grams of heroin, 5 pounds of marijuana, 213 oxycodone and fentanyl pills, 11 grams of mushrooms, 6 grams of cocaine, 12 rifles and handguns and $13,000. John Aguilar, The Denver Post, "10 arrested in bust that yields drugs, guns, cash from northern Colorado crime ring," 13 Sep. 2019 In May, Denver voted to decriminalize all possession, use, and growth of hallucinogenic mushrooms. Olivia Goldhill, Quartz, "Oregonian activists are laying the legal groundwork for therapeutic magic mushrooms," 16 Aug. 2019 The wild mushroom grilled cheese with tomato bisque ($13) is decadent and packed with fungi (yes, that’s a good thing). Daliah Singer, The Know, "Review: Officers Club serves up sophisticated, retro vibes in a former airplane hangar," 10 Dec. 2019 Recent Examples on the Web: Verb As the population mushroomed by 4% to 5% each year in the early 2000s, the borough mayor called for a study of police powers. Kyle Hopkins, ProPublica, "Looking for Alaska’s Rural Police Force? Check the Suburbs.," 5 Dec. 2019 As the population mushroomed by 4% to 5% each year in the early 2000s, borough officials called for a study of police powers. Anchorage Daily News, "Looking for Alaska’s ‘rural’ state police force? Check the fast-growing Mat-Su Borough.," 5 Dec. 2019 In recent years, that number has mushroomed to more than 524,000. Lance Hernandez, The Know, "For first time, Eldorado Canyon State Park ponders requiring reservations," 16 Sep. 2019 Crucial calls made in the final minute of the Dolphins-Jets game and the 49ers-Saints showdown in a wild Week 14 were overshadowed by the Patriots’ mushrooming problems. Arnie Stapleton, The Denver Post, "Patriots go from very back luck to very bad look," 10 Dec. 2019 The cartel's expansion into smaller, unexpected communities began to mushroom about five years ago as U.S. intelligence analysts tracked its movements far beyond border towns and major hubs. Beth Warren,, "A ruthless Mexican drug lord’s empire is devastating families with its grip on small-town USA," 25 Nov. 2019 Last month, Pope Francis chose Bishop DiMarzio to investigate the Buffalo, N.Y., diocese, where Bishop Richard J. Malone has come under criticism for his handling of a mushrooming clergy abuse scandal. Ed Shanahan, New York Times, "Bishop Named by Pope to Investigate Abuse Is Accused Himself," 13 Nov. 2019 Mold grew on bathroom ceilings but also mushroomed from behind the grout of the tiles. Sig Christenson,, "Family fled sewage-contaminated house on San Antonio base," 24 Nov. 2019 The claim mushroomed on Facebook at the end of public hearings on Thursday, even as Fox News played on the American Forces Network, which broadcasts to armed forces and their families. Washington Post, "NOT REAL NEWS: A look at what didn’t happen this week," 22 Nov. 2019

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

6 Jan 2020

Cite this Entry

“Mushroom.” The Dictionary, Merriam-Webster Inc., Accessed 17 January 2020.

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More Definitions for mushroom


How to pronounce mushroom (audio)

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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Comments on mushroom

What made you want to look up mushroom? Please tell us where you read or heard it (including the quote, if possible).


a plan in which a last survivor takes all

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