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 glassful (audio) \ noun
glassless \ ˈglas-​ləs How to pronounce glassless (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 restaurant will open at 11 a.m. Luca Italian Cuisine Fantastic Italian food, a nice glass of wine, and a wonderful view of downtown Cleveland as well. Marc Bona, cleveland, "50-plus Northeast Ohio restaurants opening today for patio-outdoor dining," 15 May 2020 The company used 200 acres for its new campus-like headquarters — more than 2 million square feet of office space in low-slung buildings with blue-mirrored glass, designed to hold 5,000 to 6,000 employees. At A Great Price, ProPublica, "Sears’ Headquarters Was Supposed to Turn a Sleepy Suburb Into a Boomtown. It Never Happened.," 15 May 2020 For phase one, the beer garden will have limited seating, restricted service and no refillable glasses, said Eric Schmitt, director of communications for Friends of Hoyt Park. Kathy Flanigan, Milwaukee Journal Sentinel, "'People are just so hungry to hang out': The beer garden at Hoyt Park opens Friday, with limits," 15 May 2020 All skiers must wear masks, gloves and goggles or glasses, the resort said. oregonlive, "Timberline Lodge, ski area to reopen May 15 with limited operations," 13 May 2020 But for the 68% of adults in the Canada who wear glasses, the answer is a bit more complicated. Eliza Huber,, "Face Mask Fogging Your Glasses? Here’s A Quick Fix," 7 May 2020 At Johns Hopkins, Hosey told me, the glass windows of patients’ rooms now feature handwritten notes about their occupation or the names of their grandkids. Marion Renault, The Atlantic, "The Pandemic Is a Perfect Storm for ICU Delirium," 5 May 2020 Since the 1990s, Hutch has provided top-quality chains, watches, glasses, medallions and more to its customer base. Branden Hunter, Detroit Free Press, "Detroit rapper raises money to buy Gov. Whitmer her own pair of 'Buffs'," 5 May 2020 The back of the phone is plastic, not glass, and comes in Black, White, Blue, and Pink. Ron Amadeo, Ars Technica, "The Galaxy A51, Samsung’s $399 iPhone SE fighter, gets a wide US release," 4 May 2020 Recent Examples on the Web: Verb 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 In the main room, framed by a glassed-in kitchen manned by chefs in white, an enormous skylight pulls in and diffuses the Southern California rays. Bill Addison,, "Is Spago relevant? Our critic talks through three (very different) recent meals," 27 June 2019 Jennifer Colliau’s brainchild is on-trend and forward-thinking with canned cocktails, juices clarified via centrifuge and a glassed-in prep area that would be at home at either Din Tai Fung or Jurassic Park. San Francisco Chronicle, "Why bar food in the Bay Area has never been better," 8 Nov. 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

22 May 2020

Cite this Entry

“Glass.” Dictionary, Merriam-Webster, Accessed 3 Jun. 2020.

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More Definitions for glass


How to pronounce Glass (audio)

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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More from Merriam-Webster on glass

Thesaurus: All synonyms and antonyms for glass

Rhyming Dictionary: Words that rhyme with glass

Spanish Central: Translation of glass

Nglish: Translation of glass for Spanish Speakers

Britannica English: Translation of glass for Arabic Speakers Encyclopedia article about glass

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