Longman Dictionary of Contemporary English
The Collaborative International Dictionary
Surface tension \Sur"face ten"sion\ (Physics) That property, due to molecular forces, which exists in the surface film of all liquids and tends to bring the contained volume into a form having the least superficial area. The thickness of this film, amounting to less than a thousandth of a millimeter, is considered to equal the radius of the sphere of molecular action, that is, the greatest distance at which there is cohesion between two particles. Particles lying below this film, being equally acted on from all sides, are in equilibrium as to forces of cohesion, but those in the film are on the whole attracted inward, and tension results.
Wiktionary
n. 1 (context physics English) the effect on the surface of a liquid that makes it behave as a stretched elastic membrane; it is caused by unbalanced intermolecular forces 2 (context physics English) a measure of this effect
WordNet
n. a phenomenon at the surface of a liquid caused by intermolecular forces
Wikipedia
Surface tension is the elastic tendency of a fluid surface which makes it acquire the least surface area possible. Surface tension allows insects (e.g. water striders), usually denser than water, to float and stride on a water surface.
At liquid-air interfaces, surface tension results from the greater attraction of liquid molecules to each other (due to cohesion) than to the molecules in the air (due to adhesion). The net effect is an inward force at its surface that causes the liquid to behave as if its surface were covered with a stretched elastic membrane. Thus, the surface becomes under tension from the imbalanced forces, which is probably where the term "surface tension" came from. Because of the relatively high attraction of water molecules for each other through a web of hydrogen bonds, water has a higher surface tension (72.8 millinewtons per meter at 20 °C) compared to that of most other liquids. Surface tension is an important factor in the phenomenon of capillarity.
Surface tension has the dimension of force per unit length, or of energy per unit area. The two are equivalent, but when referring to energy per unit of area, it is common to use the term surface energy, which is a more general term in the sense that it applies also to solids.
In materials science, surface tension is used for either surface stress or surface free energy.
"Surface Tension" is a science fiction short story by James Blish originally published in 1952. As collected in Blish's The Seedling Stars, it was revised to incorporate material from his earlier story "Sunken Universe", published in Super Science Stories in 1942.
Usage examples of "surface tension".
Spirlin membranes, suspended in water, increased surface tension dramatically.
The destroyers, curiously mottled with oil now, were still plunging astern, but the surface tension of the fuel held the water and spray from breaking aboard.
She tightened the brackets, keeping both little fingers under the crystal so that she could sense that surface tension.
As more and more of the glittering gas vented to the outside, the surface tension contracted the bubble into a tinier and tinier volume.
The specified mass of molten iron is released in free fall, whereupon its surface tension forms it into a perfect sphere.
Then it stuck to him, prevented from spreading outward by surface tension.
Some sort of psychic surface tension seems joined with the physical inertia one encounters just before the point of emergence.
He coiled it gently, placing the two ends of the copper against the colander-helmet just above his temples, then pressing down hard until each piece of metal broke the surface tension of the other and began to spill across the divide.
But when he poked the liquid with a fingertip, surface tension hauled it quickly into a perfect, oscillating sphere.
Without any gravity to speak of, tears upwelled and clung in quivering beads held together by surface tension.
Her waving feet abruptly touched frigid liquid, breaking surface tension with ripples that sounded oily and loud.