surface tension
1 synonym for surface tension, grouped by meaning and by how common each one is.
Noun — The force that makes the surface of a liquid behave like a stretched elastic skin, caused by the molecules at the surface pulling more strongly on each other than on the air above.
Synonyms
Rare, literary or technical
Precise, but they will stand out — check the sense before using one.
interfacial tension
How to use surface tension
The word patterns that sound natural to a native speaker.
high surface tension
reduce surface tension
break the surface tension
surface tension of water
Standard scientific term, familiar from school physics and chemistry.
Frequently asked questions
What causes surface tension?
Molecules inside a liquid are pulled equally in every direction by their neighbours, but molecules at the surface have no neighbours above them. The unbalanced inward pull draws the surface tight and makes the liquid minimise its surface area, which is why free-falling droplets are round.
What is the difference between surface tension and viscosity?
Surface tension is about the liquid's surface resisting being stretched or broken; viscosity is about how much the liquid resists flowing internally. Water has high surface tension but low viscosity; oil is the reverse.
Why does soap reduce surface tension?
Soap and detergent molecules have a water-loving end and a water-hating end. They gather at the surface and wedge between the water molecules, weakening the attraction between them — which is why soapy water wets fabric and dirt instead of beading up.
