noun, noun which may take the genitive case particle 'no'
surface activity; surface active
Technical term used in chemistry and materials science to describe the property of a substance that affects the surface tension of a liquid. Often appears in compounds like 界面活性剤 (surfactant).
This substance exhibits high surface activity.
Surfactants are often used in detergents.
界面活性 is the property, while 界面活性剤 is the substance that has that property (a surfactant).
Compound of 界面 (interface, surface) and 活性 (activity). The exact historical derivation is uncertain; the term is a modern technical coinage.