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.
For starters, the new version has a thinner texture with a much more fluid consistency than its viscous predecessor. — Beatrice Zocchi, Vogue, 18 Aug. 2026 If a black hole had a secret identity as an imperfect, energy-dissipating, viscous fluid, then an effective field theory for imperfect, energy-dissipating, viscous fluids should exist, too. — Charlie Wood, Quanta Magazine, 17 Aug. 2026 The viscous gel works by coating the walls of your pipes with a solution that eliminates the residue the flies are attracted to. — Emma Jacobson, Bon Appetit Magazine, 13 Aug. 2026 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 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 1 Sep. 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
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