viscous

adjective

vis·​cous ˈvi-skəs How to pronounce viscous (audio)
Synonyms 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
viscously adverb
viscousness noun

Synonyms of 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Several celebrities and their PR teams have denounced Perez for his viscous public insults, from Khloe Kardashian, Miley Cyrus, and Lady Gaga, a former friend of Perez. — Charisma Madarang, Rolling Stone, 5 Aug. 2026 And more than half of Venezuela’s barrels are destined for the United States, where refineries in the Gulf are capable of processing its heavy, viscous form of crude, said Jungman. — Anna Cooban, CNN Money, 2 Aug. 2026 Replacing the silicon oil isn’t a simple solution, because as Kalfas says, the complicated design of viscous dampers generally requires complete removal and maintenance or replacement by the manufacturer. — New Atlas, 24 July 2026 Usually, viscous liquids stay cohesive when bubbles form, by changing shape around them. — Rohini Subrahmanyam, Quanta Magazine, 10 July 2026 See All Example Sentences for viscous

Word History

Etymology

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

First Known Use

14th century, in the meaning defined at sense 1

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

Rhymes for viscous

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Browse Nearby Words

viscounty
viscous
viscously
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Cite this Entry

“Viscous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/viscous. Accessed 7 Aug. 2026.

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Kids Definition

viscous

adjective
vis·​cous ˈvis-kəs How to pronounce viscous (audio)
1
: having the characteristic of stickiness
2
: having or marked by viscosity

Medical Definition

viscous

adjective
vis·​cous ˈvis-kəs How to pronounce viscous (audio)
1
: having a glutinous consistency and the quality of sticking or adhering : viscid
2
: having or characterized by viscosity
a viscous flow

More from Merriam-Webster on viscous

Nglish: Translation of viscous for Spanish Speakers

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