noun, often attributive
\ ˈglas How to pronounce glass (audio) , ˈgläs \

Definition of glass

 (Entry 1 of 4)

1 : any of various amorphous materials formed from a melt by cooling to rigidity without crystallization: such as
a : a usually transparent or translucent material consisting typically of a mixture of silicates
b : a material (such as obsidian) produced by fast cooling of magma
2a : something made of glass: such as
(1) : tumbler also : glassware
(2) : mirror
(3) : barometer
(4) : hourglass
b(1) : an optical instrument or device that has one or more lenses and is designed to aid in the viewing of objects not readily seen
(2) : field glasses, binoculars usually used in plural
c glasses plural : a device used to correct defects of vision or to protect the eyes that consists typically of a pair of glass or plastic lenses and the frame by which they are held in place

called also eyeglasses, spectacles

3 : the quantity held by a glass container
5 : crystal meth specifically : a pure form of crystal meth


glassed; glassing; glasses

Definition of glass (Entry 2 of 4)

transitive verb

1a : to provide with glass : glaze sense 1
b : to enclose, case, or wall with glass the sunroom was glassed in
2 : to make glassy
3a : reflect
b : to see mirrored
4 : to look at through an optical instrument (such as a pair of binoculars)


biographical name (1)
\ ˈglas How to pronounce Glass (audio) \

Definition of Glass (Entry 3 of 4)

Carter 1858–1946 American statesman


biographical name (2)

Definition of Glass (Entry 4 of 4)

Philip 1937–     American composer

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Other Words from glass


glassful \ ˈglas-​ˌfu̇l How to pronounce Glass (audio) \ noun
glassless \ ˈglas-​ləs How to pronounce Glass (audio) \ adjective

Synonyms for glass

Synonyms: Noun

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Examples of glass in a Sentence

Noun The waiter filled our glasses with water. She drank two glasses of water. She was wearing dark glasses with thick black frames.
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Recent Examples on the Web: Noun The areas of heavier snow, to add insult to injury, will endure one or two more cold days until the snow melts, because fresh snow cools the air much like ice cubes cool a glass of water. Katy Read, Star Tribune, "Overnight snowfall could bring 2 to 6 inches to southern Minnesota," 27 Feb. 2021 Aided by a glass of red wine, former House Speaker John Boehner added some colorful comments while recording the audio version of his upcoming memoir, including some choice words for Sen. Ted Cruz. William Cummings, USA TODAY, "Ex-House Speaker John Boehner, recording memoir's audio, gives Ted Cruz some colorful advice," 26 Feb. 2021 Choose a glass of vermouth, prosecco, or a cocktail, and watch as the crowd gathers and voices rise. Patricia Doherty, Travel + Leisure, "The History of the Aperitivo — and How to Enjoy It Like an Italian," 26 Feb. 2021 Add to the meal a glass of wine to softly intoxicate the senses, and relaxation is guaranteed. Michael Alpiner, Forbes, "Dr. Deepak Chopra Partners With CIVANA Wellness Resort And Spa," 26 Feb. 2021 Guzzling iced coffee or hot tea, enjoying a glass of red wine, or consuming saucy dishes may have started to do a number on your teeth—or, at the very least, affected the brightness of your smile., "Shoppers Swear By This Snow Teeth Whitening Kit for Brightening Smiles at Home," 25 Feb. 2021 Just look at a typical Bay Area restaurant menu, where a glass of good wine might cost $13 and a craft beer might be $7. Esther Mobley, San Francisco Chronicle, "Gen Z is making fun of Millennials on TikTok for drinking wine. They've got it all wrong," 25 Feb. 2021 This electric adjustable desk model is made of steel and topped with glass. Hanna Horvath, NBC News, "8 best standing desks of 2021, according to experts," 24 Feb. 2021 There’s also a Lover’s Bubbly Brunch (which comes with a free glass of sparkling wine) on Feb. 20 and 21. Sarah Blaskovich, Dallas News, "Can we get a do-over? Dallas restaurants celebrate Valentine’s Day and Fat Tuesday a week late," 23 Feb. 2021 Recent Examples on the Web: Verb The plan was simple: Walk out to points of long ridges and glass open areas below. Jace Bauserman, Outdoor Life, "Worth the Wait: It Took 10 Years, but a Mother-Daughter Team Finally Killed Two Massive Colorado Mule Deer," 23 Dec. 2020 Years ago, the industry switched from metal backs to glass in order to facilitate wireless charging, since the RF signals couldn't penetrate metal. Ron Amadeo, Ars Technica, "Pixel 5 teardown shows off the guts of Google’s latest flagship," 2 Nov. 2020 There, several glassed-in enclosures contained multiple cubs, the couple says. Matt Wake |, al, "‘Tiger King’: Alabama ties to bonkers Netflix hit," 17 Apr. 2020 Throughout the night, Wolf zipped between the gleaming glassed-in kitchen and the dining room, touching both the tables of regulars and strangers like me. Adam Erace, Fortune, "Charleston Restaurant is the most relaxed formal dining experience in Baltimore," 8 Mar. 2020 Fit hunters glassing the Salmon River’s breaks in spring can find multiple bears on any given evening. Andrew Mckean, Outdoor Life, "The Best Black Bear Hunting Unit in the Word," 2 Apr. 2020 But some of the small glassed-in study rooms have at least four students grouped around the table, putting them much closer than six feet from each other. Alec Macgillis, ProPublica, "What’s It Like on One of the Only University Campuses Still Open in the U.S.?," 26 Mar. 2020 Colglazier was glassing when dawn broke on the Kansas rifle season. Scott Bestul, Field & Stream, "The Best Bucks of December 2019," 7 Jan. 2020 Carson’s glassed-in kitchen, perched above the entrance, overlooks the whole scene like a command center. Los Angeles Times, "Review: At Bon Temps in Downtown L.A., the brilliant desserts are only the beginning," 29 Aug. 2019

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


before the 12th century, in the meaning defined at sense 1


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

History and Etymology for glass


Middle English glas, from Old English glæs; akin to Old English geolu yellow — more at yellow

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Time Traveler for glass

Time Traveler

The first known use of glass was before the 12th century

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Statistics for glass

Last Updated

2 Mar 2021

Cite this Entry

“Glass.” Dictionary, Merriam-Webster, Accessed 3 Mar. 2021.

Style: MLA
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More Definitions for glass



English Language Learners Definition of glass

 (Entry 1 of 2)

: a hard usually transparent material that is used for making windows and other products
: a drinking container made out of glass
: the amount held by a glass container



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

: to fit, protect, or enclose (something) with glass


\ ˈglas How to pronounce glass (audio) \

Kids Definition of glass

1 : a hard brittle usually transparent substance commonly made from sand heated with chemicals
2 : a drinking container made of glass
3 glasses plural : a pair of glass or plastic lenses held in a frame and used to help a person see clearly or to protect the eyes
4 : the contents of a glass a glass of milk


noun, often attributive
\ ˈglas How to pronounce glass (audio) \

Medical Definition of glass

1a : an amorphous inorganic usually transparent or translucent substance consisting of a mixture of silicates or sometimes borates or phosphates formed by fusion of silica or of oxides of boron or phosphorus with a flux and a stabilizer into a mass that cools to a rigid condition without crystallization
b : a substance resembling glass especially in hardness and transparency organic glasses made from plastics
2a : an optical instrument or device that has one or more lenses and is designed to aid in the viewing of objects not readily seen
b glasses plural : a device used to correct defects of vision or to protect the eyes that consists typically of a pair of glass or plastic lenses and the frame by which they are held in place

called also eyeglasses

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