surfactant

noun

1. A surface-active agent, or wetting agent, capable of reducing the surface tension of a liquid; typically organic compounds having a hydrophilic “head” and a hydrophobic “tail”.

   “Dr. Khorana added that this is especially true of cleansers that feature surfactants like sodium lauryl sulfate, as this class of ingredients can cause “dryness, irritation and eczema.””

2. A lipoprotein in the tissues of the lung that reduces surface tension and permits more efficient gas transport.

   “It is conceivable that impairment of surfactant proteins is due to rheological and immunodefensive disorders of testis and epididymis or prostate.”