vis·​cous | \ ˈvi-skəs How to pronounce viscous (audio) \

Definition of viscous

1 : having a thick or sticky consistency : viscid viscous secretions viscous corn syrup
2 technical : having or characterized by a high resistance to flow viscous lava

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Other Words from viscous

viscously adverb
viscousness noun

Synonyms & Antonyms for viscous



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Examples of viscous in a Sentence

viscous syrup that takes forever to pour from a narrow-neck bottle
Recent Examples on the Web The head could also have collected more like 200 grams of material, the low end of the team’s estimates, perhaps thanks to the surprising behavior of the asteroid’s viscous surface. Chris Wright, Wired, "How NASA Scrambled to Save OSIRIS-REx From Leaky Disaster," 16 Dec. 2020 Today, shampoo usually takes the form of a viscous liquid. Julie Ricevuto, Allure, "The Science of Beauty: How to Use the 7 Types of Shampoo," 25 Nov. 2020 In the second, countless nanobots floated inside vials of viscous liquid, each roughly as small as a bacterial cell. Lexi Pandell, Wired, "The Future of Work: ‘Remembrance,’ by Lexi Pandell," 20 Nov. 2020 In one scene of the Crown episode, a woman exits a frenzied emergency room, steps out into the viscous fuzz of daytime, and is smashed by an oncoming bus. Cynthia Gorney, National Geographic, "Decades ago, this pollution disaster exposed the perils of dirty air," 27 Oct. 2020 In its pure form, viper venom is viscous and golden, resembling a light honey. Myles Karp, Smithsonian Magazine, "The Lab Saving the World From Snake Bites," 21 Oct. 2020 The dirtiest oil, like the viscous stuff from Canada’s tar sands, has to be steamed out of the ground and heavily refined before being shipped off to the coast. Michael J. Coren, Quartz, "Global fuel standards are pushing the dirtiest oil out of the market," 12 Oct. 2020 The syrup hurricane, viscous and lethal, stalled out over the town of Chewandswallow for three days. Charlie Dektar, The New Yorker, "Chapter Books Rewritten to Reflect the Catastrophic Effects of Climate Change," 15 Sep. 2020 Depending on its composition, lava ranges from 10,000 to 100 million times as viscous as water. Cody Cassidy, Wired, "How to Escape From an Erupting Volcano," 8 Sep. 2020

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

14th century, in the meaning defined at sense 1

History and Etymology for viscous

Middle English viscouse, from Anglo-French viscos, from Late Latin viscosus full of birdlime, viscous, from Latin viscum mistletoe, birdlime; akin to Old High German wīhsila cherry, Greek ixos mistletoe

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Time Traveler for viscous

Time Traveler

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

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Statistics for viscous

Last Updated

19 Dec 2020

Cite this Entry

“Viscous.” Dictionary, Merriam-Webster, Accessed 21 Jan. 2021.

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More Definitions for viscous


How to pronounce viscous (audio)

English Language Learners Definition of viscous

of a liquid : thick or sticky : not flowing easily


vis·​cous | \ ˈvis-kəs How to pronounce viscous (audio) \

Medical Definition of viscous

1 : having a glutinous consistency and the quality of sticking or adhering : viscid
2 : having or characterized by viscosity a viscous flow

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