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


ropy (also ropey), syrupy, thick, viscid


runny, soupy, thin, watery

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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

Enhancements to the engine relative to the 50i's unit include a block made of a new aluminum alloy, a viscous damper on the crankshaft, stronger pistons and piston rings, and an iron coating on the cylinder walls. Daniel Golson, Car and Driver, "The 2020 BMW X5 and X7 Get New M50i Performance Variants," 22 May 2019 The paint forms various viscous filaments, which are thrown against a vertical canvas. Jennifer Ouellette, Ars Technica, "Study: modern masters like Jackson Pollock were “intuitive physicists”," 26 Dec. 2018 Counterfeit cold medicines are often made out of a nasty concoction known as diethylene glycol (DEG), which is a clear, colorless, odorless, viscous liquid with a sweet taste. David Grossman, Popular Mechanics, "This Simple Musical Instrument Can Detect Poison," 13 Sep. 2018 If the board and shareholders accept Husky’s bid, the combined companies would have a large set of oil production, pipelines and refineries in western Canada’s oil sands, a region where viscous oil is abundant but expensive to produce. Russell Gold, WSJ, "Husky Makes Unsolicited Bid to Fellow Canadian Oil Firm MEG," 30 Sep. 2018 This also lowers the number of flare-ups on the grill because mayo is less viscous than oil. David Kaplan, Fox News, "This simple mayonnaise-based grilling hack will change your summer cookouts," 4 July 2018 One day in late May 2016, Roger Stone — the political dark sorcerer and longtime confidant of Donald Trump — slipped into his Jaguar and headed out to meet a man with a Make America Great Again hat and a viscous Russian accent. Manuel Roig-franzia And Rosalind S. Helderman,, "Trump associate Roger Stone reveals new contact with Russian national during 2016 campaign," 17 June 2018 The Dawn spacecraft identified an unusual peak called Ahuna Mons that some have suggested is a cryovolcano, erupting viscous water ice. John Timmer, Ars Technica, "Ice volcanoes have likely been erupting for billions of years on Ceres," 18 Sep. 2018 Oxygen-Depleted Blood This darker, viscous blood is made for smearing (á la the shower curtain in Psycho). Gabriella Vigoreaux, Good Housekeeping, "How to Make Fake Blood for Halloween," 31 July 2018

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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Statistics for viscous

Last Updated

1 Jun 2019

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Time Traveler for viscous

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

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More Definitions for viscous



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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More from Merriam-Webster on viscous

Rhyming Dictionary: Words that rhyme with viscous

Thesaurus: All synonyms and antonyms for viscous

Spanish Central: Translation of viscous

Nglish: Translation of viscous for Spanish Speakers

Britannica English: Translation of viscous for Arabic Speakers

Comments on viscous

What made you want to look up viscous? Please tell us where you read or heard it (including the quote, if possible).


to move with exaggerated bouncy motions

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