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viscous

/ˈvɪs.kəs/
IELTSAcademic
adjective

Viscous means thick and sticky, so a liquid does not flow easily. It is often used for oils, gels, and other dense substances.

  • The sauce was too viscous to pour quickly.
  • Honey is more viscous than water.
  • The machine needs viscous oil.

Adinary Nuance

Viscous is more precise than thick, and more technical than sticky. Writers use it for liquids and materials that flow slowly, not for objects or general heaviness. In science and business writing, it sounds more exact than everyday words like runny or syrupy.

In other languages

Vietnamese
sệt
Spanish
viscoso
Chinese
黏稠的
Japanese
粘性のある
Korean
점성이 있는

Etymology

Viscous comes from Latin viscum, meaning "birdlime" or a sticky substance. It entered English in the 16th century with the idea of being thick and sticky.

Common phrases

viscous liquidviscous fluidhighly viscousviscous substance

Synonyms

Related words

Frequently asked questions

Is viscous the same as thick?
Yes, but viscous is more specific. It usually describes a liquid that flows slowly.
Is viscous formal or scientific?
It is fairly formal and common in science, engineering, and academic writing.
Can I use viscous for food?
Yes. You can describe sauces, honey, or syrup as viscous.