vis·​cous ˈvi-skəs How to pronounce viscous (audio)
: having a thick or sticky consistency : viscid
viscous secretions
viscous corn syrup
technical : having or characterized by a high resistance to flow
viscous lava
viscously adverb
viscousness noun

Example Sentences

viscous syrup that takes forever to pour from a narrow-neck bottle
Recent Examples on the Web All works are linked by an expansive approach to production, pushing the material at every stage—from ashes and sand to viscous fluid to solid forms—into new visual and conceptual spheres. Elle Decor Editors, ELLE Decor, 11 May 2023 In either case, Performance models more effectively direct the resulting ruckus to the pavement through a new clutch-type limited-slip differential that replaces the outgoing viscous unit. Dan Edmunds, Car and Driver, 16 May 2022 Look for rich-textured creams, thick, hydrating gels, and viscous oils. Jessica Teich, Good Housekeeping, 3 Aug. 2020 To the untrained ear, a hydrothermal vent — or more precisely, a vent from the Suiyo Seamount southeast of Japan — generates a viscous, muffled burbling that recalls an ominous pool of magma. Star Tribune, 21 Nov. 2020 Again, this may have something to do with Erebus magma being that much more viscous. Erik Klemetti, Discover Magazine, 26 July 2011 Sticky and viscous like molasses, hyrax urine hardens quickly in air. Elise Cutts, Scientific American, 14 Mar. 2023 Another Cadillac exclusive is a viscous torque-converter clutch, which locks up earlier, yet more smoothly, than a conventional design does. Csaba Csere, Car and Driver, 16 Mar. 2023 The activity can improve muscle function around the joints and encourage the body to produce more of what’s called synovial fluid, a viscous liquid that lubricates the joints. Caroline Hopkins, NBC News, 7 Mar. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'viscous.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

Dictionary Entries Near viscous

Cite this Entry

“Viscous.” Dictionary, Merriam-Webster, Accessed 2 Jun. 2023.

Kids Definition


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

Medical Definition


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

More from Merriam-Webster on viscous

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