green·house | \ˈgrēn-ˌhau̇s \

Definition of greenhouse 

(Entry 1 of 2)

1 : a structure enclosed (as by glass) and used for the cultivation or protection of tender plants

2 : a clear plastic shell (such as a canopy) covering a section of an airplane also : a compartment (as for a bombardier) enclosed by such a shell



Definition of greenhouse (Entry 2 of 2)

: of, relating to, contributing to, or caused by the greenhouse effect greenhouse warming greenhouse gases

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Synonyms for greenhouse

Synonyms: Noun

conservatory, hothouse

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Examples of greenhouse in a Sentence


needed to move the plants into the greenhouse before the first frost killed them

Recent Examples on the Web: Noun

The global divestment movement has urged universities, pension funds and national sovereign wealth funds to pull their money out of coal, oil and other fuels that contribute to the greenhouse gases responsible for global warming. Somini Sengupta, New York Times, "Ireland Moves to Divest From Fossil Fuels," 12 July 2018 Some in the agency were concerned that not doing so could lead to lawsuits against the EPA for failing to regulate greenhouse gases, which in 2009 were determined to pose a threat to human health. Mark Trumbull, The Christian Science Monitor, "From new leadership to Clean Power Plan, subtle shifts ripple through EPA," 11 July 2018 Transportation, the single largest source of greenhouse gases, saw a 2 percent increase in emissions as fuel consumption rose in 2016. Dale Kasler, sacbee, "California beats its 2020 goals for cutting greenhouse gases," 11 July 2018 Summers are growing warmer in most U.S. cities as increasing amounts of greenhouse gases such as carbon dioxide add heat to the atmosphere, Climate Central says. Bruce Henderson, charlotteobserver, "Sweaty days are on the rise in Charlotte, and they can send you to the hospital," 11 July 2018 Plastics depend on petrochemicals for manufacturing, adding to greenhouse gases that are a primary cause of climate change. Jon Talton, The Seattle Times, "Starbucks ditches straws, but our plastic addiction is much bigger," 10 July 2018 Kavanaugh was skeptical of several of the Obama administration’s environmental regulations, including efforts to limit greenhouse gases and hazardous air pollutants. David G. Savage,, "Brett Kavanaugh, a Washington veteran, is Trump's second pick for the Supreme Court," 10 July 2018 In 2007, the Supreme Court ruled that the Clean Air Act required EPA to come up with a plan to curb emissions of greenhouse gases. Anchorage Daily News, "EPA’s acting administrator has long lobbying record on issues before the agency," 5 July 2018 That’s because its main ingredient, the potent greenhouse gas methane, has been leaking from oil and gas facilities at far higher rates than governmental regulators claim. Warren Cornwall, Science | AAAS, "Natural gas could warm the planet as much as coal in the short term," 21 June 2018

Recent Examples on the Web: Adjective

In the case of Harvey, as with other specific events, scientists now have the capability to perform attribution studies which make more quantitative statements about how greenhouse gas emissions influenced that event. Suzana Camargo, Fortune, "Global Warming Didn’t Cause Hurricane Harvey. Here’s What Did.," 29 Aug. 2017 The worse mileage a vehicle gets the more greenhouse gas emissions flow into our atmosphere. Gary Richards, The Mercury News, "Mr. Roadshow: Why is she bragging about her polluting old car?," 6 Mar. 2017 Several independent analyses, including authoritative studies from the Department of Energy’s Argonne National Laboratory in Illinois, suggest that ethanol releases significantly less greenhouse gas emissions than gasoline. David Gelles, New York Times, "The Standoff Between Big Oil and Big Corn," 17 Sep. 2016 The school was able to cheaply heat its greenhouse year-round with cord wood cut by students., "New Alaska Handbook Provides How-to on Heated Greenhouses," 12 May 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'greenhouse.' 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 greenhouse


1664, in the meaning defined at sense 1


1974, in the meaning defined above

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Phrases Related to greenhouse

the greenhouse effect

Statistics for greenhouse

Last Updated

11 Oct 2018

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Time Traveler for greenhouse

The first known use of greenhouse was in 1664

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More Definitions for greenhouse



English Language Learners Definition of greenhouse

 (Entry 1 of 2)

: a building or part of a building that has glass walls and a glass roof and that is used for growing plants



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

: relating to or caused by the warming of the Earth's atmosphere that is caused by air pollution : relating to or caused by the greenhouse effect


green·house | \ˈgrēn-ˌhau̇s \

Kids Definition of greenhouse

: a building with clear walls and roof (as of glass) for growing plants

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