Function Keys are also heavily used in the BIOS interface. Generally during the power-on self-test, BIOS access can be gained by hitting either a function key or the delete key. In the BIOS keys can have different purposes depending on the BIOS.
Freebase(0.00 / 0 votes)Rate this definition: Surfactant. Surfactants are compounds that lower the surface tension of a liquid, the interfacial tension between two liquids, or that between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming agents, and dispersants.
lung surfactant, a detergent-like agent that reduces the surface tension of the liquid film covering the inner lining of the pulmonary alveoli. As an alveolus becomes smaller during expiration, the surfactant becomes more concentrated, further reducing the surface tension and preventing alveolar collapse.