ce·​ment | \ si-ˈment also ˈsē-ment \

Definition of cement

 (Entry 1 of 2)

1a : concrete
b : a powder of alumina, silica, lime, iron oxide, and magnesium oxide burned together in a kiln and finely pulverized and used as an ingredient of mortar and concrete also : any mixture used for a similar purpose
2 : a binding element or agency: such as
a : a substance to make objects adhere to each other
b : something serving to unite firmly justice is the cement that holds a political community together— R. M. Hutchins
3 : cementum
4 : a plastic composition made especially of zinc or silica for filling dental cavities
5 : the fine-grained groundmass or glass of a porphyry


cemented; cementing; cements

Definition of cement (Entry 2 of 2)

transitive verb

1 : to unite or make firm by or as if by cement Pebbles were cemented together by clay. has cemented his role as a leader on the team— T. W. Smith
2 : to overlay with concrete cemented the cellar floor

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Other Words from cement


cementer noun

Synonyms for cement

Synonyms: Noun

adhesive, bond, glue, size

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Examples of cement in a Sentence


There is a layer of cement under the bricks. what kind of cement works best on glass and pottery?


A win would cement her reputation as a strong competitor.
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Recent Examples on the Web: Noun

As brilliant and as motivated as these young people are, others must come forward to level the road bed, mix the cement and smooth the tar. Steve West, Sun-Sentinel.com, "Innocence lost, power found | Opinion," 8 May 2018 Saturday night has made the rest of this opening series a metaphor for Whiteside's career and Heat future, an opportunity for him to either flip the narrative on him or see the cement on that narrative harden. Greg Cote, miamiherald, "This Heat season - and his own wavering future - depend on Hassan Whiteside rising up | Miami Herald," 16 Apr. 2018 Reducing the amount of cement in this way consequently reduces CO{-2} emissions. The Economist, "Making buildings, cars and planes from materials based on plant fibres," 14 June 2018 The docks go on forever, seemingly endless paths of cement along an infinite supply of food. Sean Patrick Cooper, The New Republic, "Is America Ready for the Next Superstorm?," 4 June 2018 Of those, 70 were allowed into the San Ysidro port on Thursday after spending four nights camped out on the cement in Tijuana just outside the gate. Daniel González, azcentral, "Migrant caravan: 158 Central Americans now admitted to apply for asylum in U.S.," 3 May 2018 Elmwood Park Vandalism Profanity and obscene pictures were reported drawn on the cement April 18 at Bambi Park, 2815 N. 74th Ave. Deborah Kadin, chicagotribune.com, "Police reports: Profanity, obscene pictures drawn in cement at park in Elmwood Park," 30 Apr. 2018 Many structures with thin cement walls and corrugated tin roofs have been flattened or rendered otherwise uninhabitable. Ben Otto, WSJ, "Drinking Water, Fuel in Short Supply in Indonesian Quake Zone," 7 Aug. 2018 Plus there’s a special cement crown on top of the chimney. Kevin Dupzyk, Popular Mechanics, "So You Want To Fix Your Chimney," 21 Dec. 2018

Recent Examples on the Web: Verb

Years in the making, the launch cemented SpaceX's initial lead in the new space race with the success of the most powerful rocket in the world, complete with booster-landing ballet. David Grossman, Popular Mechanics, "One Year On, the Falcon Heavy's Successful Launch Is Still Incredible," 6 Feb. 2019 And in August, Beijing officially cemented the ban just days after President Xi Jinping gave a speech about myopia and authorities recommended curbing video games as one of the solutions. Shannon Liao, The Verge, "China lifts video game ban but not for its biggest player," 29 Dec. 2018 Kelly Sullivan/Getty Images for LinkedIn LinkedIn co-founder Reid Hoffman has burst onto the leaderboard of political donations in the age of Trump, cementing his status as a powerbroker in Silicon Valley politics. Theodore Schleifer, Recode, "Reid Hoffman is learning an early rule of being a megadonor: It’s hard to keep track of your money," 26 Dec. 2018 The style grew quickly in popularity, especially among the French upper class, and following Napoleon's invasion of Russia, became a go-to for the Russian Tsars as well, cementing its status as an elite beverage. Lauren Hubbard, Town & Country, "Everything You Need to Know About Brut Champagne," 21 Dec. 2018 The first Men in Black film (1997) was an instant classic and pretty much cemented Will Smith's status as a mega-star. Jennifer Ouellette, Ars Technica, "Thor Ragnarok stars reunite, kick alien butt in MiB International trailer," 20 Dec. 2018 In addition to the Times profile, Saarinen would get the cover treatment from Time magazine in 1956, cementing his celebrity status. Patrick Sisson, Curbed, "Why Eero Saarinen’s ‘50s office was a breeding ground for modernist design," 8 Nov. 2018 The president has cemented the GOP’s legacy as one of reaction and reality denial. Brian Flood, Fox News, "Hurricane Florence: Washington Post declares Trump is 'complicit' for dangerous storm," 12 Sep. 2018 This should be a time of celebration for Aldrin and a moment to cement his legacy. Eric Berger, Ars Technica, "Buzz Aldrin returns to Twitter, sues his son and former manager," 23 June 2018

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


14th century, in the meaning defined at sense 1a


14th century, in the meaning defined at transitive sense 1

History and Etymology for cement


Middle English sement, from Anglo-French ciment, from Latin caementum stone chips used in making mortar, from caedere to cut

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Statistics for cement

Last Updated

10 Feb 2019

Look-up Popularity

Time Traveler for cement

The first known use of cement was in the 14th century

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More Definitions for cement



English Language Learners Definition of cement

 (Entry 1 of 2)

: a soft gray powder that is mixed with water and other substances to make concrete
: the hard substance that is made when cement is mixed with water and allowed to dry
: a substance that is used to make things stick together



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

: to join (things) together with cement
: to make (something) stronger


ce·​ment | \ si-ˈment \

Kids Definition of cement

 (Entry 1 of 2)

1 : a powder that is made mainly from compounds of aluminum, calcium, silicon, and iron heated together and then ground and mixed with water to make mortar and concrete
3 : a substance used to make things stick together firmly


cemented; cementing

Kids Definition of cement (Entry 2 of 2)

1 : to join together with or as if with cement There were sheets of ice … cementing the tops of the hemlocks in arches.— Jean Craighead George, My Side of the Mountain
2 : to make stronger The experience cemented their friendship.


ce·​ment | \ si-ˈment \

Medical Definition of cement

1 : cementum
2 : a plastic composition made especially of zinc or silica for filling dental cavities

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More from Merriam-Webster on cement

Rhyming Dictionary: Words that rhyme with cement

Thesaurus: All synonyms and antonyms for cement

Spanish Central: Translation of cement

Nglish: Translation of cement for Spanish Speakers

Britannica English: Translation of cement for Arabic Speakers

Britannica.com: Encyclopedia article about cement

Comments on cement

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very full or close together

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