It is an element that serves to cause a surface tension. The term is of English origin. It is equivalent to surfactant. In medicine it is a substance present in the pulmonary alveoli that help prevent atelectasis (complete or partial collapse of the lung).
SURFACTANT Anglicism derived from SURFACE ACTIVE AGENT, or surfactant, name by which it is designated to elements that cause surface tension on others or that are surface tensioned. The Spanish name is surfactant or surfactant